Thought I would share this article. Certainly worth a read if you freeze in front of a crowd. Doesn't matter if it is an internal meeting or a seminar, stage fright can ruin any message you are trying to convey.
There are basically apps for any issue you may have with public speaking. A lot of the apps have been designed for the professional in mind. For example, you can even get a teleprompter - the sort news readers rely on - if you keep drawing a blank.
Problem 1: You're nervous in front of crowds. Solution: Upload your PowerPoint and practice in front of an interactive audience with VirtualSpeech's Public Speaking. The app may require a virtual headset (see: Google Cardboard), but its realistic, 3-D scenarios are top-notch for training. Free for iOS and Android.