01 6–8 weeks
Catalog or content app
Information lookup, no transactions or complex accounts.
Mobile app development
iOS and Android through publication in both stores. The last one we built and maintained has more than two million active users across ten countries.
2M+ active users on the last one we built · 4 apps published on the App Store and Google Play · 10 countries in simultaneous operation
- React Native
- Expo
- iOS
- Android
- Push notifications
- In-app payments
- Store submission
Built on
An engineering team that has already been on the other side.
Ninety seconds: who we are, how we work and what you get at the end.
An agent that takes the event, decides and leaves a record
An email, an order or an alert comes in. The agent queries your systems, decides by your rules, asks for approval when needed and executes. Pick a case and watch it run.
Example: a customer asks what their policy covers. The system answers with the exact page of the contract and opens the case.
01Event arrives
Does it cover theft from a public car park?
context
product = motor_premium
02Plans
Queried · policy 88213
Read · clause 4.3
Decided · open a claim
Queried · CRM
Queried · price list
Drafted · proposal
Read · invoice 9902
Cross-checked · PO-4471
Detected · discrepancy
03Queries the systems
Policy_wording_2026.pdf84 pp
Motor_exclusions.pdf12 pp
Claims_email1,240
ERP · policies38,400
Price_list_2026.xlsx118 rows
CRM · opportunities2,310
Proposals_202556 PDF
Sales_email4,800
Supplier_invoices3,900 PDF
ERP · purchase_orders4,110
Framework_contracts.pdf22 docs
Payments_email2,100
84 pp → 612 chunks
04Human approval
Asked for approval · human
ApproveReject
05Executes and logs
- Queried · policy 88213
- Read · clause 4.3
- Decided · open a claim
- Asked for approval · human
- Executed · created the case in the ERP
- Queried · CRM
- Queried · price list
- Drafted · proposal
- Asked for approval · manager
- Executed · sent and logged
- Read · invoice 9902
- Cross-checked · PO-4471
- Detected · discrepancy
- Escalated · human
- Logged · case opened
log · 5 steps · who and when
Swipe to follow the flow →
The app is half the work
01
Store review
Apple rejects for reasons that are on no obvious checklist, and each rejection costs days. You need to know what they check and prepare the submission for it.
02
Developer accounts
Apple charges USD 99 a year, Google USD 25 once. They must be in your company’s name: if they belong to whoever built the app, the app is not entirely yours.
03
OS updates
Every year iOS and Android change things that break apps. An unmaintained app stops working on its own within about two years.
04
Signing certificates
Losing the Android signing key means never being able to update the app again. They are handed to your company and documented.
01
How we work
One codebase, two platforms
React Native for most cases: a single codebase for iOS and Android, so the team maintains one app instead of two. Native only when the case genuinely demands it — heavy graphics, intensive sensor use, very specific system integrations — and we justify it before proposing it.
And mobile almost never comes alone: it needs backend, authentication, push notifications, payments or integration with what you already have. We build that too, so you are not coordinating two vendors who blame each other when something breaks.
We work from Medellín with companies across Colombia, and remotely with teams in the United States and the rest of Latin America. Publishing to the App Store and Google Play happens under the company’s own accounts, wherever it is based.
Formats
What a mobile app costs
Price is driven by three things: how many features it has, how many systems it connects to, and whether it needs its own backend. Here are the scopes and their timelines; the range for your case comes out of the free 15-minute call.
02 10–16 weeks
Transactional app
User accounts, payments, notifications, own backend.
03 4–6 months
Full platform
App, admin dashboard and integrations with existing systems.
Before investing this
If your idea is not yet validated with real users, an app is a very expensive way to find out.
In many cases it is better to start with a mobile web experience or even a WhatsApp flow, confirm people use it, and build the app once you know which features matter.
Related services
Software development
Custom software development
The system around the model, not just the model.
Integrations and APIs
Connecting the systems that do not talk today
MCP servers against the systems already in operation.
AI chatbots and assistants
Chatbots for businesses of every size
With the evaluation set run before it ever reaches production.
AI consulting
AI consulting for enterprises
Architecture, evaluation criteria and cost per query before writing code.
Key takeaways
Four things before the call
- 01
Building the app is half the work: the other half is store review, developer accounts, signing certificates and annual maintenance.
- 02
An unmaintained app stops working on its own within about two years, because iOS and Android ship yearly versions that break things.
- 03
Quarl uses React Native for most cases — one codebase for iOS and Android — and native only when the case genuinely demands it.
- 04
If the idea is not yet validated with real users, an app is a very expensive way to find out: a mobile web experience or a WhatsApp flow costs a fraction.
This is where the data comes in
An AI system is worth what its sources are worth. These are the standard connectors; anything with an API or a database connects the same way, and what has no API is handled by file.
SAP
Enterprise ERP
Oracle
ERP and database
NetSuite
Cloud ERP
Salesforce
CRM and service
HubSpot
CRM and marketing
PostgreSQL
Database and pgvector
Microsoft SQL
Database
Snowflake
Data warehouse
BigQuery
Google data warehouse
Databricks
Data platform
Redshift
AWS data warehouse
Synapse
Azure data warehouse
Supabase
Managed Postgres
Workday
Payroll and HR
QuickBooks
Accounting
Sage
Accounting and ERP
Xero
Cloud accounting
Shopify
Catalogue and orders
WooCommerce
Catalogue and orders
Magento
Catalogue and orders
Stripe
Payments and subscriptions
Google Drive
Documents and folders
CSV y Excel
Flat files
Nothing in this category
A RAG system in production: three years, two million users
We built and operated the assistant for a loyalty platform serving more than two million active users across ten countries.
We built the full pipeline: document ingestion and normalization, chunking, embedding generation, vector store on Azure AI Search and Pinecone, and retrieval with grounded generation on LangChain.
We held it above 99% availability for three years.
RAG systems →Frequently asked questions
01 React Native or native?
React Native for most cases, because a single codebase for iOS and Android is the difference between one project and two, in cost and in maintenance. Native when the case demands it: heavy graphics, intensive sensor use, very specific OS integrations or extreme performance requirements. We justify it with concrete reasons before proposing it.
02 How long until we are in the stores?
Build time depends on scope, six weeks to six months. App Store review usually takes one to three days, but a rejection adds days and sometimes weeks if it forces product changes. Google Play is faster. We prepare submissions for Apple’s review criteria, which is where most projects get stuck.
03 Whose name are the developer accounts in?
Your company’s, always. It seems like a minor detail and it is not: if the accounts belong to the vendor, you cannot change vendors without losing the app and its reviews. We set the accounts up in your name from the start and hand over documented access and certificates.
04 What about maintenance?
Every year iOS and Android ship versions that break things, and the stores raise their minimum requirements. An unmaintained app stops working on its own within about two years. So maintenance is not optional; who does it is. Your internal team can carry it with the documentation and access we hand over, or you can leave it with us under contract. Annual cost usually runs 15% to 20% of build cost, and it is the one service of ours we recommend not skipping.
05 Do you include the backend?
Yes. An app almost never lives alone: it needs authentication, an API, a database, push notifications and sometimes payments. We build it end to end so you are not coordinating two vendors who blame each other when something breaks.
06 Can you add AI features to our app?
Yes, and it is one of the highest-value combinations we see: an in-app assistant with the user’s context and permissions, semantic search over your content, or data extraction from the camera. We apply the same measurement discipline as in any AI project.
07 What if our idea is not validated yet?
We will suggest not building the app yet. Validating with a mobile web experience or even a WhatsApp flow costs a fraction and tells you which features actually matter. Building the app afterwards, knowing that, is cheaper than building it twice.
Fifteen minutes. A concrete answer.
It gets fixed, it gets built, or it is not worth it. And if the diagnostic does not reach three actionable findings, it is not charged.