Welcome to Android Central! My Nexus 5 doesn't get particularly hot unless I'm doing a lot of processor-intensive things. I think the main time I've noticed it get hot is when I just got it and was installing a ton of apps.
Which Droid do you have--the Ultra, Mini, or Maxx? Check your Battery stats to see if any particular app seems to be working overtime--that could lead to heating up. Occasional reboots can also help. You may also want to consider wiping the cache partition, which won't erase any personal data: Wipe Cache Partition - DROID Mini / DROID Ultra / DROID Maxx by Motorola