You can sign up for a free account here - FollowerFilter.com. Unlike its competitors, the free version is quite comprehensive. The only limit is 100 unfollows a day. If you pay them the $2.99/mo you erase that limit plus the ads go away. The ads aren't even intrusive, either.
Unfollow the Dead Weight
Yup, like its competitors, FollowerFilter lets you look through the people you are following who aren't following you back. You can determine if you can stop following some of them. You can sort by their last post date, their number of followers, and more. It doesn't show you the actual last post on the screen like some others do, but it's still quite useful. That information is just a cut-and-paste away. Unfortunately you can't actually just "click" on the account to see their details, for some reason. You have to cut and paste the shown account name into a new browser manually. This is definitely a down-side of this tool.
If there are people you are following who haven't posted in four years, maybe it's time to give up on them. Your ability to follow is not unlimited, after all. You want to follow as many people as you can who are in your genre. That way you build relationships and can retweet important posts that your audience will find useful. It's time to prune off those people who stopped using their account and, instead, follow people who are active.
People Following You that You Aren't Following Back
Then we have the other side of the coin. The people who are following you. Are you not following them back? Why? Is it because they're a spammer? These are the people you should block or unfollow. You don't want to keep them on your lists. We all get the porn and marketing followers linking to us as their way to get new business. Unless you do want to do business with them, close that door.
One option to find healthy accounts to follow back is to sort the list by latest post so you can see who's active. Look at those active people and see if they're a good person to follow or a spammer to block. See those green buttons? Those are people following me who I havenít followed back yet. Those are the accounts for me to look at.
Another choice is to filter by number of followers, to see if there are large accounts you can follow back.
In general, you do want to follow back all legitimate accounts, as part of the TweetKarma.
So, to summarize, FollowerFilter is a solid program with full-featured functionality for free. If you don't mind ads, and you don't need to unfollow more than 100 people a day, this is a great option. You do have to log into each account separately, but if you have multiple accounts you might want to work on one each day and cycle around. That way each one gets some attention regularly and your list grows!
Building Traffic for your Twitter Account
Followers and Twitter's Value
What is a Twitter Hashtag?
Maintaining Multiple Twitter Accounts
Choosing a Twitter Icon
Choosing a Twitter Background
What is a Twitter Hashtag?
Twitter for Authors
Twitter Promotion Tips
Twitter Next Step
Twitter 2000 Follower Limit
TweetDeck - Free App for Twitter
TrueTwit - Prevent Twitter Spam
Tweepi - Manage your Followers
ManageFlitter - Follow and Unfollow
FollowerFilter - Great Free Follower Management Tools
Twitter Template Designs
Spring Twitter Template Design
Summer Twitter Template Design
Autumn Twitter Template Design
Winter Twitter Template Design
BellaOnline Twitter Template Design
Taking on Twitter by Kathi Browne
Twitter Business and Pleasure by Erwin Calamer
Lisa's Twitter Feeds
LisaLowCarb Twitter Profile Follow @LisaLowCarb
LisaSheaAuthor Twitter Profile Follow @LisaSheaAuthor
LisaSheaArtist Twitter Profile Follow @LisaSheaArtist
LisaVideoGames Twitter Profile Follow @LisaVideoGames
WineIntro Twitter Profile Follow @WineIntro
BellaOnline Twitter Profile Follow @BellaOnline
LisaShea Twitter Profile Follow @lisashea
SuttonMass Twitter Profile Follow @SuttonMass
RomanceClass Twitter Profile Follow @RomanceClass
MusedReview Twitter Profile Follow @MusedReview
LisaSheaOrigami Twitter Profile Follow @LisaSheaOrigami
WeddingsLisa Twitter Profile Follow @WeddingsLisa
ASPIsFun Twitter Profile Follow @ASPIsFun
EnjoyMA Twitter Profile Follow @EnjoyMAWebsite
BookKitten Twitter Profile Follow @BookKittenTweet
BostonWritersM Twitter Profile Follow @BostonWritersM
BVArtAssoc Twitter Profile Follow @BVArtAssoc
FarFromEdenBand Twitter Profile Follow @FarFromEdenBand
FreeBargainBook Twitter Profile Follow @FreeBargainBook
LisaShea_HiVol Twitter Profile Follow @LisaShea_HiVol
OrganizeIdeas Twitter Profile Follow @OrganizeIdeas
PermaFreeBooks Twitter Profile Follow @PermaFreeBooks
What Does It Cost to Ghostwrite a Book?
Lisa Shea's Editing Services
Lisa Shea Free Ebooks
Lisa Shea Full Library of Published Books
Getting Your Book Published
Writing Tips and Online Books
Lisa Shea Medieval Romance Novels
Online Literary Magazines
Lisa Shea Website Main Page
You Can Get Free Gift Cards For Shopping, Searching and Discovering What's Online at Swagbucks.com