Did you read through the thread @Mikeyv1986 ? The best thing you can do is make sure you're not sharing your password with anyone.
If the app has crashed for you, then there's a chance that it may take a few minutes for that crashed session to release.
If after 6 minutes you still can't get a stream then someone definitely has access to your account. You'll need to change your password, and then wait for them to stop their stream - there's currently no way to kick them off (even we can't do it).
We're working on improvements to this now, so that changing your password will result in existing sessions being terminated within 30 minutes.