They were pretty clear about why the app is no longer free. More than likely keeping it free would end in "no more support."

It's only $1, so now would be a good time to give them the dollar and then forget it happened if you are so inclined.

There are apps out there that are way less stable and way less well supported, yet want loads of money or even subscriptions to use (hello Trillian,) so I think if you really like this app, you'd be more than willing to reward its creators by giving them their meager requested sum of 99 cents, which they are getting only a fraction of after Google takes their cut.

Or live with ads and deal with it if you're that woefully stingy.