i use a small android phone and want to use T9 keyboard again. i tried this app called Tappy https://play.google.com/store/apps/details?id=app.minibytes.keyboard&pli=1 , but the customization options are limited. it is not open source, and the developer is unwilling to open-source it (i emailed him).

i swear i remember using a good one on my htc hero like 12 years ago. does anyone know of any?