App development FAQ: 20 questions before you hire

The short version

Price and time depend on the screens, the systems to connect and the AI work. Ask for the scope, the delivery date and the monthly running costs in one quote.
Open the server, AI, App Store and Google Play developer accounts in your company's name in week one.
Put source code ownership in the contract, and ask to see a working build every week.

The questions owners ask before they sign

These 20 questions come from two places: what people in Thailand type into Google before hiring an app developer, and what buyers ask us before they sign. They fall into four groups: price and time, scope and technology, working together, and after handover. Each answer is short and links to the page that explains it in full.

Price questions are answered with the factors that move the price, because two apps that sound alike can differ a lot in screens and connected systems. For a rough figure on your own project, describe it to Dream in our chat. This page is chapter 9 of AI for business: a guide from benefits to building.

Price and time

1. What does an app cost, and what decides the price?

The price depends on the number of screens and steps users go through, the AI features and the existing systems the app must connect to; we fix it in a quote once you approve a clickable prototype.

2. How many weeks does an app take?

A web app usually takes 4 to 8 weeks. For a mobile app, the time depends on the screens and the systems it connects to; larger work is split into phases, and the delivery date goes into the quote before work starts.

3. How long do App Store and Google Play reviews take?

Apple says it typically reviews at least half of submissions in under 24 hours and 90% in under 48 hours; Google says reviews for certain developer accounts can take up to seven days, or longer in exceptional cases. If an app is rejected, the team fixes what the store names and resubmits, and every later update is reviewed again. Open the developer accounts in your company's name in the first week, because Apple asks an organization for a D-U-N-S Number, and a new personal Google Play account must run a closed test with at least 12 testers for 14 days before it can publish.

4. Is there a maintenance cost after handover?

Yes, if you choose to have us look after the app: a monthly care plan, with its scope set in the quote. Apps need an update at least once a year, because both systems release a new version every year and Google Play requires apps to target a recent Android version; an app that falls behind can't be installed by new users on newer phones.

5. Who pays for servers and AI usage?

The app owner pays for these, under your accounts or ours, as agreed in the contract: cloud servers and databases, AI model usage, the yearly Apple Developer Program membership, the one-time Google Play registration, and extras such as maps or SMS. AI usage is billed by the number of calls and the length of the text or documents the model reads, so we estimate your monthly usage before work starts.

Scope and technology

6. Should we build an app, a web app or a LINE Mini App?

Build a web app when the main users are staff at computers, or when you want to change things at once without waiting for store review. Build an app when customers open it often and need the camera, GPS or push notifications. Build a LINE Mini App when customers should order, book or collect points straight away with nothing to install.

7. Flutter or React Native?

We choose native or cross-platform for each project; for cross-platform, we pick Flutter or React Native by the team that will maintain the app and the systems it connects to.

8. Can we launch on iOS and Android at the same time?

Yes: one codebase goes to the App Store and Google Play in the same round, though each store reviews it separately, so the release days can differ slightly (see question 3).

9. What kind of AI can go into an app?

The common ones are a chat assistant that answers from your company documents, search and product recommendations, reading documents and photos with OCR, and voice commands, each built on LLMs and RAG.

10. Will the AI in the app give wrong answers, and how is that controlled?

It can, so we have it answer from documents you approve (RAG), set guardrails that stop answers outside its scope, hand the conversation to your staff when it is unsure, and test it with real customer questions before launch.

11. Is customer data safe, and how do you follow PDPA?

We handle personal data under PDPA and work under an NDA, and when data cannot leave the company, the AI can run on your own servers (question 12).

12. Can the system run on-premise?

Yes: we install the backend and the AI model on your own servers as a private LLM, so the data stays inside your organization.

Working together

13. What should we prepare before talking to a developer?

The problem you want to solve, who will use the app, the systems it must connect to, and examples of the documents or screens you use today are enough; the technical spec gets written with you while we build the prototype.

14. How does the work run?

Our work runs in five steps: understand the job, design until you approve the prototype, build in sprints with a demo every week, test, then launch and look after the app under a monthly plan.

15. Can we see the work while it is being built?

Yes, from before any code is written: you click through the prototype and approve the screens first. After that you see a demo of working software every week.

16. Is the team your own staff, or do you subcontract?

DNA Maker's own team does all the work; we pass nothing to other companies or freelancers, and the people you meet on day one are the people who build it.

After handover

17. Who owns the source code?

Source code and documents are delivered as set out in the contract, and the app is published under your developer accounts or ours, as agreed in the contract.

18. Can you take over an app another company built?

Yes. We review the existing code and documents first, then propose the scope and price. For an app, collect four things from the previous team: the latest source code, the documents that exist, access to the servers and database, and the store accounts that hold the app. If the app sits in the previous team's account, both Apple and Google have a procedure to transfer it to your company's account without taking it off the store.

19. Can we add features later?

Yes, and we suggest it: keep the first version to what users need, then choose the next features from the usage data in the analytics installed at launch. Each new batch of features gets its own fixed scope and price. For a large project we always offer a smaller first phase. Every update goes through store review again (question 3), so group changes into releases.

20. Do you have work we can look at?

Yes. The same team has delivered 500+ projects for Thai banks, hospitals and large corporate groups. The portfolio shows the doctor-training management app for BDMS MSO and the SCG Express delivery app prototype, and School Plus has a demo on the school management page.

What we put in the quote

Most questions on this page have a clear answer only once we know who will use the app and for what. DNA Maker starts by talking to the people who will use it, such as sales, service or field staff, and writes down the user flows, the systems to connect and the points where the AI must stop for a person to decide. That is how the scope, the delivery date and the price are fixed before any code is written.

You click through a prototype before you approve it and see a working demo every week. The team is our own, with no subcontracting. We build iOS and Android apps with AI, web apps and LINE Mini Apps connected to the systems you already run, and deliver the source code as scoped. See AI App Development, or describe your project to Dream in our chat for an estimate within minutes.

SOFTWARE ENGINEERING GLOSSARY

Software engineering glossary

Term	What it is	A simple example	What executives should ask the development team
Prototype	Clickable mock screens you can try before any real code is written	Sales staff click through the ordering steps on a phone and ask to move a button before approving	Does the prototype cover every step users take, or only the main screens?
RAG	A way for the AI to search your company documents before it answers, instead of answering from the model's memory	The in-app assistant answers warranty questions from the latest product manual	When a document changes, how soon do the AI's answers change, and who updates it?
Guardrail	Rules that check the AI's questions and answers and stop it when it goes out of scope	The AI won't quote special prices and passes the customer to a salesperson	When the AI is unsure, who does it hand over to, and can we see the log?
Source code ownership	The rights to the system's code and documents, as set out in the contract	After the final payment, the company has all the code in its own Git account	Does the contract say which code is ours and which is a shared library?
Vendor lock-in	Being unable to change who maintains a system because the code, accounts or knowledge sit with one vendor	The app sits in the developer's store account, so every change of team needs their permission	If we change teams one day, what must we get from the current one?

SourcesApple Developer, App Review
Apple Developer, Enrollment (organizations and the D-U-N-S Number)
Apple Developer, Overview of app transfer
Google Play Console Help, review times for app submissions
Google Play Console Help, app testing requirements for new personal developer accounts
Google Play Console Help, target API level requirements
Google Play Console Help, transfer apps to a different developer account

Try this tomorrow: On one sheet of paper, list the five accounts your app uses or will use: server, database, AI provider, Apple developer account and Google Play account. Next to each, write whose name it is in and who holds the password. For any line in a person's name or the developer's name, ask your developer when it will move to your company, and use questions 5 and 17 above to start that conversation.