Idumpvitastuff over at reddit released Hidden Applications for Vita 3.63 owners. This tool leverages the recent release of psvimgtools that allows some nice tricks on firmwares 3.63 and 3.61 (which do not have access to a full hack such as HENkaku on firmware 3.60).
This app will in particular let you enable Sign Up for PSN, which technically lets you do account switching. This also enables the package installer, but that one will refuse to start on retail Vitas.
The author gave a full tutorial on how to enable Hidden Applications on PS Vita 3.63
2. Obtain your CMA Key. Just enter your AID (the random letters and numbers where your CMA backups are stored.) and it will give you the key
3. put the PSVIMGTools in the same folder you extracted CreateBackup.zip
4. Run the BuildScript for your OS. either the win32 one of osx/linux depending on what you have
5. Paste/Enter your CMA Key and press enter
6. Copy the “HIDENAPPS” folder into your CMA Backups/APP Folder
7 Refresh CMA Database, and restore backup to your vita
We’re expecting more cool tricks to be revealed for 3.61 and 3.63 owners, as more and more people tinker with psvimgtools in the days or weeks to come. Yifan lu has stated that tricks such as custom bubbles (PSP usermode homebrew, VHBL), PS TV whitelisting, or registry hacks such as X/O button swapping should be doable on these firmwares with psvimgtools.