Here you'll find some informations about tweaking your Samsung Avila (Tocco) S5230. Note that I'm not responsible for any damage to your phone, use at your own risk.
Short review. Pros:
Cons (mostly minor):
Because newest Trekbuddy is signed with Thawte certificate and S5230 is missing that, TB will work as unsigned application but every time you start application system will ask you confirmation to access memory card. Unfortunately it is not possible to install new certificates straight from the phone, you can only view currently installed certificates, to do that go: Menu → Applications → Games and more → More (bottom bar) → Certificates → Third parties. You should see something like this:
To install Thawte (as well as any other certificate) you'll need to download firmware (currently s5230xpik5) and modify part of it. Unpack the firmware, there should be a file with
.ffs extension, this is an image of TFS4 filesystem which is FAT compatible. I used WinImage software (shareware, usable for 30 days) to modify the firmware; if you're using Linux loopmount this image:
mount filesystem.ffs /mnt/samsung_image -t vfat -o loop
Please note that I didn't test it under Linux. Next step is to download Thawte root certificates (you may enter anything in the form) and find
Thawte Code Signing CA.cer file. But before coping that certificate, remove one of wallpapers or any other unneeded file - for some unknown reason (probably size mismatch) flash software refuses to program if you not free some space before coping the certificate (look in
SystemFS\Media\Images). Now copy certificate to
Security\Domain3Certs. Save changes and flash new firmware (I didn't use that guide, but it's a good start). Now your phone should have new certificate and Trekbuddy will install correctly:
There's also tkfileexplorer which can be used to view internal memory of the phone but I was unable to find path where certificates could be stored (probably they're copied somewhere else). In settings you must guess COM port number for the phone if you're using USB (try COM3 first).