There are many sites out there listing all the new features of iOS7. The list below is personal – it comprises things that I personally noticed during my first few days using the new OS on my iPhone and iPad.
If you set a 4-digit passcode on your device, under iOS6, if you typed an incorrect passcode, a message appears telling you so. With iOS7, the device simply buzzes
The icon for the alarm clock/stopwatch/timer now has a live, real-time, albeit analogue, clockface.
The telecoms-provider (O2 in my case) signal strength indicator is now made up of white dots rather than white bars
The Music app now displays cover art (where available) for each album and track. However, you still can’t change the font of the track names so long track names end with …
Calendar – to switch to “list view”, you have to tap the magnifying glass icon at the top, which I didn’t find intuitive
Photos in the Photos app are organised by date by default. If you click the Albums icon at the bottom of the app they display based on albums, which I find more logical
When in a GPRS area (i.e. no WiFi, no 3G), instead of seeing a white dot, the iPhone now displays the letters GPRS at the top of the screen
You can display the times that your text messages were sent and received by holding your finger down on the screen of a text message “conversation” and dragging your finger to the left
Call blocking is now available. From the Phone app, tap Favorites or Recents, click the I (information) icon next to the person/number and scroll down to the bottom where you will see “Block this Caller”. You can also do it from the Contacts icon (in the Phone app, not the Contacts app itself) by tapping the name of the contact and scrolling down.
To delete a individual text message (rather than an entire conversation as I did!!), tap and hold on the message, tap the “speech bubble” and tap “more…”