Build to android: 23Mb for 2 buttons start screen?

Hi, I was testing out the “build for android” button on Unity.
I created a single gui texture for the background of my start screen and placed 2 gui textures that will act as buttons to “start” and “quit” accordingly.
Then, I push the Build to android button, and the .apk it´s huge: 23 Mb
I´ve seen complex games in .apk for under 10Mb.
Do I have to Delete my “standar assets” & “Mobile assets” folders from the project?
Also I did applied javascript to event the buttons as “onMouseEnter” (yipity-yapity here);
But the touchscreen on android won´t activate them when I push them.
Please help me to size down the .apk.
Thanks.

Are you using a basic or pro mobile license? The pro licenses enable some better stripping options, as listed on the license comparison chart.

Past that, try this: Unity Manual: Reducing File Size

I deleted all mobile assets folders along with the default assets folder. Builted. the file output was 6mb. So i setup one new level (blue bacground, and a plane. This time bloated back to 25 mb.

I deleted all mobile assets folders along with the default assets folder. Builted. the file output was 6mb. So i setup one new level (blue bacground, and a plane. This time bloated back to 25 mb.