Emacs font size issue

Well I downloaded and installed Emacs from fdroid.
The thing is on the default installation the font size is very very small and it is too small to be read.

Zooming does not work.
I went to the author’s website and I could not find anything about the installation on Android.

Can someone please suggest me a way to increase the font size so that I could work my way from there? If setting the font to a bigger size is permanently possible it would be great.

Thanks in advance