A handy guide from Nokia on their secret codes for the following handsets.
5320, 5700, 5800, 6110 Navigator, 6120, 6124 Classic, 6210 Navigator, 6220 classic, 6650, 6680, E-Series, E51, E61i, E63, E65, E66, E70, E71, E72, E75, E90, N70, N73, N76, N77, N78, N79, N80, N81, N82, N85, N91, N92, N93, N93i, N95, N95 8GB, N96, […]

Unable to install a protected application from an untrusted supplier - If you experience this one then try to follow the instructions below:

First you need to go to ->
menu - settings - application mgr. - installation settings and change software installation to “all”, but beware some software might harm your phone.
Then download the Samsung i850 […]

If you want to squeeze as much battery life as possible from your Nokia 5800 XpressMusic, here are some hints and tips on how to do it:

Fully charge the phone’s battery.
Do not switch the phone off while on charged.
Shut down unnecessary applications. The fewer apps that run simultaneously, the longer the battery will last.
Turn down […]