Should I call back debt collectors who had the wrong number?

Should I call back debt collectors who had the wrong number? What are some good password managers other than LastPass or Dashlane? Is there a way I can get the "FREE" HTC one from AT&T and then flash it to become the same phone that Google is selling for $650? What does everyone think of the Chromecast? What free programs can you guys recommend for editing mp3 tags and info? I need an easy-to-use finance tracker. Is there some better way of evaluating the signal strength from the carriers at my ...