Just to let you know, installing an app launcher and additional apks still works on firmware version 11.2.2 (based on Android 4.4.2 instead of 4.0.4 for versions up to 10.x). However, you'll probably need a new boot.img to install with fastboot (at least I didn't dare to use the one linked here from the rooting package for version 1.9.0 since it was not my device). I found a script on
https://forum.alles-ebook.de/showthr...t-img-und-WLAN that lets you generate a suitable custom boot.img for every tolino model and firmware from the official update.zip you can download from
https://mytolino.com/service/updates/ for your device.
Edit: If you're using KOReader, updating might not be the best idea at the moment. Whereas KOReader works really well on 10.x, it's not really usable on 11.2.x due to the missing screen refresh described in
https://github.com/koreader/koreader/issues/3517.