It may well be that your iPad simply needs to be restarted in order to clean up the system memory.
Optional App Report
You can force the app to quit (which may result in losing information about your last trip or pin drop) and send a crash report to Apple by forcing it to quit in a specific way:
- Press and hold the power button on the top until "Slide to Power Off" appears
- Don't slide to power off.
- While "Slide..." is showing, press and hold the Home button.
This will force a "crash" to let Apple know exactly where the Maps app caused you to feel it needed a "force quit" and might help the engineers fix a bug if that's the cause.
Restarting the iPad
- Press and hold the power button on the top until "Slide to Power Off" appears.
- Slide to power off.
- Turn the iPad back on by pressing and holding the power button until the Apple logo appears.
The iPad 2 needs a power off less often due to the extra memory it has, but both devices occasionally need the user to force quit a problematic app as well as a clean reboot.
If these don't solve the problem then I'd go with the other suggestions here, but a clean restart may well fix things.