One more thing...

Problem: It works extremely crappy with Bluetooth connection, e.g. my Sony 1000X, but works fine with wire connection and wired headphones only. Hope you can fix this issue soon!

But as to wired headphones in-ear seems to be better than over- or on ear ones. I tested it with Sony XBA-A3. This app do a good job with 3D off (Must off- this is extremely bad for music playback), 40% intensity on, auto equalizer on, which really gave a sense of real amplifier (not quite but close).

I just hope you guys fix the Bluetooth boost soon. Then, it will be perfect.

VerdictSandy about Boom: Bass Booster & Equalizer, v1.2