In Chord Perfect - When I play the E note, thickest string, the app is not recognising the note.
Same with the tuner, it does not recognise the E note. I have no problems tuning it (or it being recognised) with Guitartuna though.
Really sorry @Alexeyd I don’t know what you mean. I probably should say that I am a newbie to guitar so any reply will need to be in put across as if I don’t know much (which is in fact true).
Using the harmonic at the 12th as @Alexeyd suggests is probably the best idea. Rest you finger very lightly exactly over the 12th fret - don’t press, just the lightest touch. Then pluck the string and immediately remove your finger, if you get it right (it might take a bit of practice) you will hear a note an octave above the low E string note. It’s a purer note and more stable, tuners pick it up more easily. I’ve used this trick a lot.