Mark mail as unread
There’s a somewhat hidden way to mark messages as “unread” in the mail app: When viewing a mail,
touch the Details link in the upper right. Then find the Mark as unread link below the subject.
Access Network Monitor
If you like to see the reception status of all the cells you’re receiving, type the following code on the dialpad and press the dial button: *3001#12345#*
Recover from Recovery Mode loop
If you try to update the firmware, you might be stuck in the “Connect to iTunes”-recovery mode although you didn’t change any bit of the firmware (e.g. because of some freakin’ errors of iTunes). You now have the choice between a long firmware+backup restore – or get your iPhone back running in about 30 seconds. The procedure is described at ihackintosh.com. Do yourself a favor and don’t try it in Windows. Installing libusb there broke something and after a reboot of Windows, all USB devices didn’t work and hat yellow exclamation marks in the Windows device manager. Under Linux, it’s easy as pie. These instructions are for Ubuntu:
- get iRecovery source code and install build-essential as well as libusb-dev
- compile iRecovery
- get the iPhone into recovery mode:
- switch it completely off, disconnect all cables
- hold down the ▢ Home button
- keep the button down while connecting it to the PC
- wait until the “Connect to iTunes” logo appears, then release the ▢ Home button
- now run:
./irecovery -s - wait for the prompt (
]) and enter the following commands: (iffsbootdoesn’t do anything, typereboot)] setenv auto-boot true] saveenv
] fsboot - your iPhone should now boot normally