Your address book is mine: Many iPhone apps take your data

Upload or Store?

Path stored the data but I know 4sq does a search against it but does not store it. That can make a huge difference...

Twitter also does it as part of the special iOS5-privileged settings panel:

http://cache.gizmodo.com/assets/images/4/2011/06/ios5twitter...

That must have had close Apple review as part of the official iOS/Twitter integration.

The explanation underneath the 'Update Contacts' button is somewhat reasonable, though it may not register with most people that, barring some unlikely fancy indirection, to 'use' email addresses and phone numbers means they're being reported to Twitter's servers.

I really think Apple needs to do something here with their next update. For every company that does the right thing by asking permission first, who knows how many are being sneaky.

As can when it happens - I think 4Square was already pretty reasonable, because they only uploaded the address book when you hit "Find my Friends using Contacts" or something like it.

Path, to me, was only particularly bad because they'd upload your contacts every time you signed in.

What if your address book was hashed (sha1, bcrypt) and then uploaded? In that case, all that would be uploaded is a list of hashes for the email addresses or phone numbers of people i know.

Then, when another person signs up for an account, it's easy to see who they should suggest they should join, but nowhere is any personal data being stored.

Sounds like it'd work to me?