There are 2 Thai based accounting programs for SME's and Freelancers. They are both web based and have an Android/iOS app.
1. Flowaccount ( https://flowaccount.com/en )
I have been using this for a few months now and does make accounting a whole lot easier. Design and layout is done very well. The english version is very extensive as well. Keep track of expenses, issue quotes, po's, billing notes, invoices/receipts, payroll.
They have a free version, but based on the features you need, a tiered pricing plan. The highest plan is 3xxx Baht per YEAR ( personally, I would've paid this amount per month, but psssst....dont tell them )
2. SME Payday ( https://www.smepayday.com/en/ )
I tried this one yesterday, as it seems to be a bit more poweful. Has all the above features and also clock-in/clock-out feature with location base. My major problem with this was that the english version is all but complete.
Main Page is in Thai and English. Registration is in Thai only. Once passed registration and login, you can switch back to English. There is enough english to navigate, but many many parts are still in Thai. I also didnt think it was as user friendly. However, it seems to have more features and customization than flowaccount and it seems the free version offers more. If you can speak and read Thai, this may be more bang for the buck Baht.
Both of these companies being startups and based in Thailand for Thai businesses, things can change / update fairly regularly, so downsides/upsides I mentioned here may have been updated since this posting. So best to check it out yourself.