$39 USD only for a licence, multi-computers per user
$0 Android and iPhone companion apps are included in price
$0 FREE upgrades and support
To support learning the product, there is the online help available in the desktop version, manuals and demos on this website under Docs & Demos or the 3 steps articles.
To sync between different computers, you just need to transfer the small data file using software like Dropbox (free and automatic), a USB key or even email it.