tweetbeep – Track conversations and mentions of you, your products, your company, interests — whatever — and get hourly updates.

appTracks: Web
appTags: keywords, online reputation management, tracking

Tweetlater – Schedule tweets, bulk upload tweets, track keywords, send welcome DMs, URL shortening, auto following, more.

appTracks: Web
appTags: auto following, direct messages, keywords, schedule tweets, tracking, url shortening

monitter - A way to monitor Twitter for keywords being used in conversation.

appTracks: Web
appTags: keywords, monitor, real-time

Tweetscan – Sends you email updates when your keywords are mentioned on Twitter, identi.ca, and other Laconica-based sites.

appTracks: Web
appTags: identi.ca, keywords, laconica, updates