Adequate, but basic

App does what it claims: you can configure various alerts for different sets of criteria based on the email headers. But the options fizzle from there: no matching the message body, no installing your own tones (not even by hacking! The tones are some proprietary format), no advanced scheduling, etc.
Also, Ive seen some emails come that should have matched, but didnt. Not sure if that might have been a cloud issue (yes, its all processed in the cloud), or just a rule-matching issue, but no way for me to know of course. If cloud-processing is a problem for you, then this app wont fly.
Given that most users probably have some mission-critical business use for this, it would be nice to have a more reliable, less cloud-oriented design. Is that asking too much for $2.99?

maitrrre about MailTones - Pager Alerts for Email and Gmail, v1.54