Financial calculators
EMI, eligibility, interest-reverse, prepayment and comparison calculators. Exact formulas that match your lending policy, with the amortisation schedule shown rather than hidden.
Mobile Apps & API Integrations
Fintech calculators, dashboards and the API plumbing that connects the systems you already pay for.
What this covers
Two halves of the same job. On one side, mobile-friendly product experiences: loan and EMI calculators, eligibility tools, booking flows and the dashboards that sit behind them. On the other, the unglamorous integration work — payment gateways, KYC, SMS, WhatsApp, CRM and lead routing — that decides whether any of it actually saves your team time.
- Calculators engineered for conversion, not just arithmetic
- Integrations that fail loudly and recover, instead of silently losing leads
- A dashboard your operations team stops maintaining in Excel
Capabilities
The specifics, rather than the adjectives.
Operations dashboards
Live pipelines, stage-wise funnels, ageing reports and exportable data. One screen that answers "where did this month go" without anyone rebuilding the answer in a spreadsheet.
Payment and KYC integrations
Razorpay, PayU, Cashfree, Aadhaar and PAN verification, penny-drop bank checks, e-sign flows. Idempotent request handling so a retry never creates a duplicate payment.
CRM, SMS and WhatsApp plumbing
Every enquiry lands in your CRM, with the source preserved. Automated acknowledgement messages, templates approved against WhatsApp policy, and a delivery log you can audit.
Lead capture that does not leak
Server-side validation, a durable record of every submission, retry on transient partner failures, and an alert when a third party starts rejecting requests.
Data handled properly
Encryption in transit, secrets kept out of the codebase, sensitive fields masked in logs, and data-minimisation decisions documented and reviewed with you.
What you get
A concrete list of outputs. If something here is not relevant to your project, it comes out of the scope and the price — we would rather agree that in writing now.
- Calculator or product-flow specification and formula sign-off
- Responsive calculator or app UI, tested on low-end Android devices
- Backend API with authentication, rate limiting and structured error responses
- Third-party integrations with retry, timeout and failure logging
- Operations dashboard with role-based access and CSV/Excel export
- Automated tests over the calculation and integration logic
- API documentation for anything a partner or your team will consume
How it runs
Five steps. You always know which one you are in.
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01
Formula & flow audit
We write the calculation down and check it against your credit policy or business rules. Getting this wrong is the most expensive mistake in this kind of build.
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02
Interface design
The calculator or flow designed at phone width first, because that is where the traffic is. Progress states, validation messages and the result screen all designed, not improvised.
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03
Integration build
Partners connected one at a time, each with its own sandbox verification and a documented failure mode.
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04
Instrumentation
Funnel events from first input to submitted application, so you can see exactly which step loses people.
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05
Handover
API documentation, credential rotation instructions and a runbook for the failure alerts.
Stack
The platforms and frameworks we build, integrate and maintain on. We would rather work in a stack your team can hire for and hand over than pick whatever is interesting this year — and where an existing platform does the job better than custom code, we will say so.
- PHP 8
- Node.js
- MySQL
- REST
- JSON Web Tokens
- Razorpay
- Cashfree
- WhatsApp Cloud API
- Twilio
- Docker
FAQs
Mobile Apps & API Integrations — frequently asked questions
Can you integrate with a system that has no documented API?
Sometimes, and we will tell you honestly when the answer is no. Where a vendor exposes only file drops or a database, we integrate at that boundary and wrap it so the rest of your stack still talks to a clean internal interface. If the only option is screen-scraping, we will flag the maintenance burden before you commit to it.
How accurate are your loan calculators?
The maths follows the reducing-balance method with the same rounding rules the lender applies, and it is verified against real sanction letters or your processing system before launch. Where your policy has exceptions — moratorium periods, part-prepayment rules, processing-fee treatment — those are modelled explicitly rather than approximated.
Do you build for iOS as well as Android?
Most of what we build is a responsive web application, which covers both platforms and every desktop browser from a single codebase. Where an app-store presence is genuinely needed, we build with React Native or wrap the web app as a Progressive Web App. Our recommendation is deliberately biased towards the cheapest thing that solves the problem.
What happens when a third-party API goes down?
Each integration has an explicit failure mode: a timeout budget, a bounded number of retries where the operation is safely repeatable, a durable queue entry so nothing is lost, and an alert to your team. The customer-facing behaviour is defined in advance — usually a clear message plus a fallback route, rather than a spinner that never resolves.
Is the data we send you treated as confidential?
Yes. We work under an NDA by default, use your sandbox credentials during development, keep secrets in environment configuration rather than source control, and mask personally identifiable fields in any log we retain. Production data is never copied to a local machine.
Related
Other services you may need: AI Enablement & Document Automation · Banking & Fintech Solutions · Backend & API Development · Legacy Application Modernisation · Web Development · Data Analytics & Web Scraping · SEO & Performance Optimization · DevOps, Testing & Cloud
Free consultation
Talk through scope for Mobile Apps & API Integrations.
Bring the problem and any constraints. You will leave the call with a scope, a timeline and a price — whether you work with us or not.
We reply within one business day. · No obligation