AppFeed.net by design provides only RSS feeds for the updates (Hence the name AppFeed), but the possibility to get notification by other means is also available thanks to ifttt online service.
For those who are new to ifttt, it is a service where users select some channels to monitor (such as an RSS feed, Twitter or Facebook post, etc), and when changes occur to those channels ifttt triggers a task (such as send an Email, Tweet a message, etc). In other word ‘If THIS happens then THAT will happen‘. (A review and a great guide for using ifttt can be found on LifeHacker).
Using this service, users can create a new task that takes as input the RSS feed provided by AppFeed.net, that can trigger whatever action the users want, I have been using it to get an email and a tweet, and it works Great.