So, I am in a similar situation. Bought temp alert several years ago, too complicated. Instead, I bought this thermostat on amazon:
http://www.amazon.com/gp/product/B001XVWWKG?psc=1&redirect=true&ref_=oh_aui_search_detailpage
I then mounted it behind my dining table. Then when I leave the motorhome, I leave my Macbook (which has a built in camera) open on the table with a wireless card in it (set to auto restart if connection fails). I installed a program on my Macbook called logmein.com. Logmein, allows me to access the Macbook and the camera that is pointed at the wall thermometer using an iPhone app.
Then every hour or so, I login and check the temps and know pups are nice and cool.