For your choice proposed a very pure tuner for acoustic and bass guitar. Try it!

6 HD Guitar Wallpapers

Bass Guitar Simulator - Fretboard map .
Learn the notes of a 22 fret bass guitar with audio.
4 & 5 string in standard bass guitar tuning.
Touch to play - virtual bass guitar.
Interactive bass guitar reference.
Easy to use great for beginners.
Scrollable neck with lock .
4 sets for sounds - Punk, new wave, studio, finger sound.

Great for working bass guitar lines.