Normally $6.89, the Pro upgrade is free until Tuesday 18th March 11:00 GMT
Juice SSH is the best SSH client for Android. It's a full color terminal and ssh client, and even the free version has support for extras like Mosh and external keyboards. Add in the great connection manager, and you have an incredible remote administration tool for Android. The Pro upgrade takes things to another level with port forwarding, AES-256 encryption backups and a code snippet library for those long commands you have to type out often. It's well worth the normal price of $7 or so, but this weekend it's free.
To celebrate 500,000 users, the folks behind Juice SSH are offering the Pro license key to anyone and everyone. Simply install the app through the Google Play Store link above, then head to their promotion page and submit your email address. You'll be rewarded with a lifetime Pro upgrade that's tied to your Gmail account, and good for an unlimited number of machines. If you're thinking that's awesome, you're right because it is.
If you need a tool like this, or are looking for a great local terminal, You need to jump on this.