Ba'Derech - בדרך

וְשִׁנַּנְתָּם לְבָנֶיךָ וְדִבַּרְתָּ בָּם בְּשִׁבְתְּךָ בְּבֵיתֶךָ וּבְלֶכְתְּךָ בַדֶּרֶךְ וּבְשָׁכְבְּךָ וּבְקוּמֶךָ.

BaDerech is an app to help you take all your physical books, scan them and read them while on the road.
You can add as many pages as you want for multiple collections, and the app will remember all "regions" on the page.
Just like you do while studying Torah.