@Jean-Marie,
It's nice to see communication on MR by a senior guy from one of the best Android reader apps. At the risk of pushing my luck ...
- On the subject of Bluetooth connected devices ... perhaps I can put in a request for you to consider adding the ability to control Mantano Text-to-Speech with the media control buttons on Bluetooth headsets (as some of your competitor reader apps already do). This would be a great help when trying to listen to books when the app buttons are not easily accessible (e.g. out walking, painting the house).
Ability to start/stop the TTS via the headset Play/Pause button would be great. If you were also able to add Forward-a-Paragraph/Back-a-Paragraph via the headset Next-Track/Previous-Track buttons, that would be even better
- How about fine-tuning the control of font-size. I love the ability to change by sliding up/down the the right edge of the screen but the jumps between one size and the next are too large to get the size I want on my phone. If it's not possible to do it via the slider an extra setting in Themes would also work OK.