Only if you want to truly grow your twitter follows should you take on TweetAdder. You will want to sit down and really walk through the application because it holds allot of bells and whistles, none of them a waste however.
Some might consider it’s $55 for a single license a bit steep ($74 if you want up to use up to 5 accounts) but if you truly use it, it will be money well spent!
TweetAdder allows you to search online Twitter profiles and/or millions of tweets themselves looking for specific subject matter. Those it finds it will systematically follow them, looking of course to get a followback. If they do followback you have the option of an automatic ‘thank you’ message. If they Don’t follow you back, TweetAdder will wait a few days before UnFollowing them..keeping you from having a disproportionate follow/followers ratio.
The app also lets you load your favorite RSS feeds and automatically feed them as daily tweets, do as many as you wish per day..automatically. You are able to Pre load tweets to go out in order or mix them up and much more.
Tons of good stuff that will help you manage and build multiple Twitter accounts automatically.