I use an RK61 one from Amazon[0]. Haven't had any problems with it. I use it quite regularly for my phone and some RasPis. I made a little bracket to hold my phone at the top of the keyboard so I can sit with it on my lap or a table and type for extended periods quite happily.

I use my phone as my primary mobile computer (I don't own a laptop anymore) and am very happy with this setup.

[0] https://www.amazon.com/Wireless-Multi-Device-Mechanical-Rech...