Which feedback service with API would you recommend?

Question

Web development

Tell me a service that could be used to collect reviews. No publicity, voting, etc. Only for myself.
You need to make a simple feedback in the application. Only GET/POST request is available.
I do not want to buy hosting and do form processing myself.
PS: I tried reformal.ru/api but the API apparently does not work for it - it does not want to log in the user, and the xml returns invalid.
Upd: Or maybe try some free service to create your own API? In fact, I just need to get feedback and put it in a sign ... the main thing is that the interface should be - look at this sign! Can you advise something in this direction?