there were several problems with the last release of YouAmp, since I have not tested the upgrade path at all. The app simply crashed if you had an older version installed beforehand, but thankfully I managed to fix them by now, so you can safely upgrade.
The next release wont get that many architectural changes but is going to be localized, and here is where you can help; if you want YouAmp translated in your language, grab this messages.pot file and put the translations of the lines beginning with msgid on the lines beneath beginning with msgstr.
But please check the repository beforehand to be sure that the translation is not there yet. You can send me the translations via email (check the About section).