About Appstem
Appstem is a full-service mobile strategy, design and development company focused on creating apps that serve a purpose. They believe that the combination of the right process and a complete team of mobile experts is the right way to develop successful apps. They examine the competitive environment and the technological aspect to develop a comprehensive list of needs, features, and requirements.
Services
Appstem Reviews
Write a ReviewObservability stack that caught three production issues before any user reported them
Adriana Voss / Director of Platform Engineering - Cascadia Digital VenturesJun 05, 2026
Project summary: Several years of incremental development had left us with a platform that was technically functional but strategically limiting. A structured rebuild was the agreed path forward.
We gave this team an aggressive timeline, a technically complex scope, and a client-side project team that was stretched thin and not always available at the speed the engagement required. They absorbed all of that gracefully. Where they needed input they were precise about what they needed and when. Where they could proceed independently they did. The result was a delivery that landed on time despite the constraints on our side, which I regard as evidence of genuine professional maturity.
Senior-level engineering presence throughout the entire project, not just during the pitch, honest and commercially fair handling of scope changes, codebase that our internal team praised on review
We underestimated the input required from our subject matter experts during the requirements phase. The team flagged this early but our resource planning did not fully reflect it — our responsibility, not theirs
Questions & Answers
Infrastructure automation that freed our developers to focus on features again
Hamza Siddiqui / Co-Founder & CEO - Karachi Software HouseMay 17, 2026
Project summary: Regulatory changes required us to rebuild our client reporting module from the ground up with full audit trail, real-time data, and a compliant data residency model.
Our previous agency had given us a platform that worked well enough to demo and fell apart under real load. This team came in, diagnosed the root causes accurately, and rebuilt the critical components without disrupting the live service. The performance improvements were immediate and measurable — page load times dropped by 60 percent, error rates dropped to near zero, and our support team has far fewer incidents to deal with. The contrast with our previous experience could not have been sharper.
Technical depth across the full stack, honest and timely communication, delivered exactly what was scoped without surprise additions to the invoice
Honestly nothing worth documenting — we went in with high expectations and they were met on every measure
Questions & Answers
A partnership that began with a single project and earned a place on our preferred vendor list
Gustavo Ferreira / VP of Technology - Amazônia Digital LtdaMay 05, 2026
Project summary: Grid modernisation funding required us to demonstrate demand-response capability. The machine learning models existed on paper; we needed an engineering partner to build and productionise them.
I came into this engagement as a sceptic. We had been through a failed implementation with a previous vendor and I had high standards for what evidence of competence looked like before I would trust a partner with our core systems. This team earned that trust progressively — through the quality of the discovery documentation, the rigour of the technical proposals, the consistency of the sprint deliveries, and ultimately the stability of the production system. I no longer lead with scepticism when recommending them.
Commercially transparent throughout — no hidden assumptions, no bill shock at the end, change requests that were fair and clearly explained rather than used as a margin-recovery mechanism
Their insistence on a detailed functional specification before development began felt like friction at the time. In retrospect, it was the reason the development phase ran without the ambiguity that has derailed similar projects for us previously
Questions & Answers
Content platform our editorial team adopted without a single escalated support request
Beatriz Cavalcanti / Chief Digital Officer - Cerrado Tech SAApr 28, 2026
Project summary: Digital service standards required all citizen-facing applications to meet accessibility and performance benchmarks that our inherited systems failed. Remediation was not viable — we needed a replacement.
We had worked with three agencies before this engagement. The comparison is not flattering to the others. What distinguished this team was a systematic approach to understanding the problem before proposing a solution — something that sounds obvious and is practiced far less often than it should be. The delivery phase ran to schedule, the codebase is clean enough that our internal engineers made positive comments during handover review, and we have not logged a critical incident in five months of live operation. We intend to use them for our next phase of work.
Delivery timeline that proved achievable rather than optimistic, estimation accuracy that reflected real analysis rather than competitive bidding, scope discipline that prevented the feature creep we had experienced before
Pipeline availability for kickoff required a few weeks of lead time — in hindsight that selection pressure means you are working with a team that is in demand for the right reasons
Questions & Answers
A partnership that began with a single project and earned a place on our preferred vendor list
Imogen Tanner / Head of Engineering - Outback Data SolutionsApr 05, 2026
Project summary: Our engineering capacity was committed to maintaining existing systems and could not absorb a net-new build of this complexity. An external partner with the right skills was the only viable option.
Six months after go-live our platform is processing three times the transaction volume we specified in the original brief. The architecture choices made during discovery accommodated that growth without remediation work. That is the difference between a team that designs for what you tell them and a team that designs for what you are likely to need. We are in conversation about a Phase 2 engagement and I expect to be using this partnership for several years.
Senior-level engineering presence throughout the entire project, not just during the pitch, honest and commercially fair handling of scope changes, codebase that our internal team praised on review
Time zone coordination required some deliberate overlap management from both sides in the first couple of sprints, after which we had an efficient async rhythm that worked for the whole project
Questions & Answers
Web development done properly — performant, scalable, and a joy to maintain
Fernanda Costa / VP of Technology - Vento Retail SAMar 27, 2026
Project summary: Peak season traffic had been exposing architectural weaknesses in our platform for two years. We could no longer afford to enter a promotional period hoping for the best.
The thing I appreciate most in retrospect is that they were honest when something was harder than expected. Twice during the project the team came to us proactively to say that a particular component needed more time to do properly and explained why cutting corners would create problems later. We gave them the time. Both decisions were correct. The resulting product is solid and we have had none of the post-launch instability that plagued our last two technology projects.
Domain knowledge that went beyond generic expertise into our specific industry, willingness to push back constructively, automated test coverage that gave us deployment confidence
Time zone difference required some adjustment to our internal communication habits but the team managed the overlap window efficiently and it never affected momentum
Questions & Answers
CMS that preserved every byte of SEO equity from the old site while adding every feature we needed
Bram de Vries / Chief Technology Officer - Windmill Tech BVMar 20, 2026
Project summary: Our client portal had been built in 2017 and had not received meaningful investment since. Clients were contrasting it unfavourably with the portals of our competitors in pitches.
Six months after go-live our platform is processing three times the transaction volume we specified in the original brief. The architecture choices made during discovery accommodated that growth without remediation work. That is the difference between a team that designs for what you tell them and a team that designs for what you are likely to need. We are in conversation about a Phase 2 engagement and I expect to be using this partnership for several years.
Deep domain knowledge that reduced the discovery overhead significantly, proactive risk identification before issues became incidents, delivery cadence that our stakeholders found reassuring
The quality of documentation they produce means our team needed to set aside dedicated review time to do it justice — a minor scheduling point rather than a genuine criticism
Questions & Answers
Blockchain expertise that came with clear explanations, not just technical jargon
Vikram Srinivasan / Head of Platform - Cascade EdTech SolutionsFeb 25, 2026
Project summary: Our field service management system had not been updated significantly in six years. Rising technician count and increasing job complexity had exposed every one of its limitations.
The thing that retrospectively seems most significant is how little drama there was. Complex technology projects tend to accumulate incidents, escalations, and tense conversations. This one did not. Problems were surfaced before they became incidents. Scope changes were handled with process rather than conflict. Risks were managed rather than avoided. That level of maturity is rare in my experience and it made the delivery feel almost effortless from our side, which I know it was not from theirs.
Collaborative culture that made the team feel like a genuine extension of our organisation, strong asynchronous communication across time zones, zero-drama handling of the inevitable mid-project changes
Their discovery process is more rigorous than we were accustomed to and required more preparation from our side than we had initially allocated — but the quality of what followed justified every hour of it
Questions & Answers
Platform engineering work that let our product teams move independently at last
Imogen Tanner / Head of Engineering - Outback Data SolutionsFeb 16, 2026
Project summary: Our audience data was fragmented across eight tools with no single identity layer. Personalisation had become impossible without first solving the data foundation.
Six months after go-live our platform is processing three times the transaction volume we specified in the original brief. The architecture choices made during discovery accommodated that growth without remediation work. That is the difference between a team that designs for what you tell them and a team that designs for what you are likely to need. We are in conversation about a Phase 2 engagement and I expect to be using this partnership for several years.
Architectural decisions designed for longevity rather than just the current brief, thorough automated test coverage, post-launch stability that validated every technical choice made during discovery
Time zone coordination required some deliberate overlap management from both sides in the first couple of sprints, after which we had an efficient async rhythm that worked for the whole project
Questions & Answers
Technically rigorous, commercially grounded, and a genuine pleasure to work with
Nora Al-Otaibi / VP of Engineering - Salam Digital SolutionsFeb 09, 2026
Project summary: Customer expectations had reset and our conversion funnel data showed precisely where we were losing them. We needed a commerce platform capable of delivering the experience our competitors already had.
The integration layer was the part of the project I was most concerned about going in. Our system landscape is complex, several of the upstream APIs we relied on were poorly documented, and two third-party vendors had a history of unpredictable response times on integration questions. This team managed all of that. They documented what the upstream vendors could not, built resilience into the integration architecture where the upstream behaviour was unreliable, and delivered a solution that works as specified in production. I could not have asked for more.
Deep domain knowledge that reduced the discovery overhead significantly, proactive risk identification before issues became incidents, delivery cadence that our stakeholders found reassuring
Their insistence on a detailed functional specification before development began felt like friction at the time. In retrospect, it was the reason the development phase ran without the ambiguity that has derailed similar projects for us previously
Questions & Answers
AI models that replaced guesswork with evidence in decisions that matter most
Lars Pfeiffer / VP of Technology - NordTech Logistik GmbHFeb 08, 2026
Project summary: A previous engagement had delivered something that worked in staging and struggled in production. We approached this project with greater rigour in vendor selection as a result.
The technical quality of the final deliverable is the easiest thing to point to. The automated test coverage is thorough, the deployment pipeline is reliable, the documentation is genuinely useful rather than ceremonially produced. But the metric I keep returning to is the number of post-launch conversations we have not had to have. No incident calls at two in the morning. No emergency patches. No retrospective discussions about what went wrong. The absence of those events is the evidence I would show to someone considering this vendor.
Clear and consistent communication adapted appropriately for both technical and non-technical stakeholders, shared tooling that gave our team real-time visibility, reliable sprint delivery throughout
Their discovery process is more rigorous than we were accustomed to and required more preparation from our side than we had initially allocated — but the quality of what followed justified every hour of it
Questions & Answers
Smart contract implementation rigorous enough to satisfy both our legal and security teams
Clémentine Aubert / Head of Digital Products - Arc-en-Ciel Digital SASJan 18, 2026
Project summary: First notice of loss processing was taking three days on average. Market benchmarks were under four hours. Automation of the intake and triage workflow was the agreed priority.
The project brief was ambitious and we had received proposals ranging from two to five times our eventual budget from other vendors. This team came back with a proposal that was commercially realistic and technically credible — and then delivered against it. That alignment between proposal and outcome is not something I take for granted. I have been on the other side of it enough times to know it requires both honesty in the sales process and discipline in delivery. We experienced both.
Commercially transparent throughout — no hidden assumptions, no bill shock at the end, change requests that were fair and clearly explained rather than used as a margin-recovery mechanism
Their discovery process is more rigorous than we were accustomed to and required more preparation from our side than we had initially allocated — but the quality of what followed justified every hour of it
Questions & Answers
Customer data platform that our revenue team now cannot imagine working without
Stephanie Coleman / SVP of Digital Strategy - Horizon Financial GroupSep 15, 2023
Project summary: Our existing platform had grown organically over several years and the accumulated technical debt was beginning to affect both performance and our ability to ship new features.
The engagement started with a discovery workshop that immediately signalled this team was different. They pushed back on two of our assumptions in the first session with evidence and a better alternative. That kind of intellectual honesty is rare and it set the tone for the whole project. Deliverables were consistently ahead of schedule, code reviews were taken seriously, and the final product is something we are proud to show enterprise clients during due diligence calls.
Consistent delivery against milestones, code quality that passed our internal review without major findings, post-launch support that felt like a partnership not a ticket queue
The volume of quality documentation they produced was genuinely impressive but also meant our team needed dedicated time to review it properly — a minor process point, not a complaint