So, if you faced any problems with custom fonts in iOS...

... such as vertical alignment issues (top or bottom unnecessary offset), you can fix it by using Apple Font tool suite:
link
And once you've installed it, use terminal to enter this command:
ftxdumperfuser -t hhea -A d font.ttf
This will create special text file which contains all font settings including ascender and descender. In my case my font from Myriad family has bottom offset, so I need to increase ascender and decrease descender. After that you could recompile font with this command:
ftxdumperfuser -t hhea -A f font.ttf