Are there any limits during the free trial?

Just a few.

The main usage limits are the length of the trial (currently 14 days), and the message cap.

If you absolutely cannot evaluate our system within that timeframe or message limit, just contact us.

There are a few other nitty-gritty limitations, put in place to help prevent spam and other system abuses:

• The number of free-form "chat" messages is limited based on your usage of other texts. I.e., if all you do is sign up to use the free-form chat texts, you won't get too far.
• There is closer automatic evaluation of the content of your text notifications to reduce the possibility of spam.

Other than that, what you get when you subscribe is pretty much exactly what you get in your trial.