This update is related both to Standard and Developer License.
Starting with this version, ‘Done’ button is replaced with ‘Save’. Both ‘Clear’ and (now) ‘Save’ buttons are moved to Action Bar and permanently displayed at the top of the screen – which is relevant only for Android version 3.0 and up. Also, for all Android versions, once the signature is captured (but still not saved), pressing ‘Back’ button will display save-or-discard warning message instead of exiting the activity.
The update is free for all Standard License customers. Developer License customers that have already purchased version 6 have update for free as well. All other existing Developer License customers have 40% discount. Just contact the sales at email@example.com regarding the free/discounted upgrade.
Read more about the Signature Capture here: Signature Capture for Android.