Very cool fretboard trainer
 

I found a very cool fretboard trainer available for 4 or 5 string bass at www.guitaraddict.net. Available for all systems including tablets and phones.

Good stuff.

For iOS, I'm using Tenuto, as recommended here on TB in another thread.

For $3.99 Tenuto does the fretboard training (note, interval) for lots of stringed instruments, as well as keys; chord, note and key signature identification; scale, interval and chord training for the ear - and a few other things. Lots of options to customize.

Is there by any chance an app that allows you to play along with songs on your phone/tablet?

i.e. you go into the app, it's the neck of a bass, you choose a song and you can then play along to it by tapping along the neck. Would love something like this tbh