So i have been using the app for chess on the ipod, and it has two modes for tactics trainer- online and offline. It registers them seperately so you are allowed to do 6 tactic problems per day on the ipod. Also you can do tactic trainer on the computer for 3 more problems

THis means that either it will get fixed or more people will use the tactic trainer, i felt sorta obliged to say this since i am a free user of this wonderful site

Sounds like it has gotten better then.  It used to be that if you started online and lost your connection then you ended up with unlimited offline.  I've become a paying user now so doesn't really matter for me