Simple and effective
I use this software almost daily at work to sign PDFs and do minor annotations. The signature portion works better than Preview (IMO) and the text annotations are sufficient for my needs.
One simple improvement:
Add a "Checkmark" button - sure, we can use a text annotation and then add the uniconde checkmark, but a simple button would significantly streamline my workflow. Maybe "click" makes a default size checkmark centered on the click location or you "drag" to draw a box to cover the checkbox and the software adds an appropriately scaled and positioned checkmark. Send thank you money my way ;-)
CzarNick2 about PDF Signer