This was just a quick side project, so I didn't research too heavily any alternatives. I've never seen Jott before, but from a cursory glance the differences are:

Jott has a monthly fee whereas Call2Record is pay as you go.

Jott is probably much more expensive unless you record a lot of audio ($4/month and $12/month compared to $1/hour)

Jott limits you to recording only up to 30 seconds of audio at a time whereas Call2Record will allow you to record for an unlimited amount of time.

Jott seems to have a bunch of other extra services and features that are built around and compliment their product.