To synchronize your address books, you need to use an add-on in Thunderbird. I like gContactSync; others speak highly of Google Contacts. Both will allow whatever groups you set up in Google's Contacts to be echoed as Lists in Thunderbird. And your Android phone will be more than happy to sync with Google's Contacts. I consider it worthwhile to run a gmail account purely for the purpose of managing an address book shared between my phone and Thunderbird. I didn't want my whole TB Address Book on my phone; most of it is made up of Contacts for whom I know an email address, but no phone number, so they wouldn't be especially useful on the phone. Hence a separate address book can be populated just with Contacts chosen carefully for their relevance to the use of a phone. Of course it can store email addresses too. To attend to your last question, probably not. Few phone manufacturers offer support for Thunderbird in their synch programs. Most of them are dire IMHO. Nokia's PC Suite was OK but they have been trying for years to roll out an inferior substitute program, Ovi Suite. Samsung devices come with Kies which is near useless.