For several days now i have been trying to figure out how or if i should buy PM upgrade to store tests from multiple days (maybe thats not worth doing). There is little info on TFP pertaining to PM cost. I finally got the free version up and running on my Kindle. But quickly learned i had to upgrade to be able to store multiple test readings. When i click upgrade it just bumps me back to my main Kindle menu page. Nothing about PM or costs of upgrading appears, nor does it appear on the PM Page of TFP. What am i missing?