Can I try it before signing up?

There are two ways to try it, and they are different things.

The demo at bionicforms.com/demo needs no account. You can build and poke at an app straight away, with three tries of the AI assistant. It is a scratch space: it is deleted after about a day. The demo is not the Free plan.

The Free plan is a real account. Sign up at bionicforms.com/signup, no card needed. Your apps stay, and you get the Free plan allowances: unlimited apps, unlimited users and guests, 10,000 entries per app and 10 GB of files.