How to make a simple CRM?

Question

Android

Look, the task in brief is as follows:
1 there is a database of potential customers, with a code, name, address, logo, GPS, etc. Stored in sql format.
2 There is a small business in which it is necessary that in Android (but preferably in IOS systems, and it is very desirable that in the browser) you can take notes on clients.
3 functionality is something like this - Google map with pins. It is necessary that if I find myself in a certain place in the city, when I open the application, it immediately recognizes which company I am in and opens the client card. In the card, we pull up data on the enterprise from our database. And there are all the notes when I applied, that they answered that they decided when they did the work and the tab on the documents (act, report, contract, invoice - generate pdf on the server if possible).
Attention to the question - what technology stack should be used for such a simple task for 2 people?
That is, in order not to block a full-fledged development, but something simpler and closer to the designers. But it is desirable to support mobile applications so as not to open the web version.

Answer 1

First of all, it is worth asking the question: how relevant is this for 2 people? Exactly how much do they need.
Perhaps Bitrix24 would be right for you.
1) The customer base can be imported via a web hook, then everything will be displayed and stored in crm entities and you can even build your own business processes (if necessary). At the same time, this year the formation of documents according to the template will be released, so here it will cover your needs with a regular mechanism .. in principle, you can even download through standard tools (he understands csv)
2) There is a mobile application for both iOS and Android, and you can develop applications for them using javascript. It turns out that you can open the application in the application and it will already find your coordinates and can compare them with the stored ones. Unfortunately, you can't do without developing an application.
Regarding the technology stack for Bitrix24: html, css, javascript (b24 will do everything else).
At the same time, you can use the cloud version (and xs about the price, maybe even the free option might work)

Answer 2

while looking towards Fluid UI, BuilderX.io and Ionic Creator
I want to create a ready-made clickable prototype into which you can eventually write real functions and eventually put real data.
Today it was advised that the creation tool work with react native. Allegedly, it will be easier to finish the application this way. Can someone say something about this? Or is ionic a completely workable option?