Manual download
Download a file on this computer or phone, send it to your classic phone by Bluetooth or USB cable, then open the file on the classic phone to install it.
Main version
Try this version first. It is the standard KeyAgain app for compatible classic phones.
Download KeyAgainMIDP 1.0 — text mode
Alternative for very old phones from around the year 2000 that use MIDP 1.0. Text interface; app available in English only.
Download MIDP 1.0 (EN)Your classic phone still needs its own internet connection, through mobile data or supported Wi-Fi, to sync with and use the KeyAgain service.
After installation, open my.keyagain.app on a computer or modern phone to connect your services and pair your classic phone.