That's one of the things we're working on right now. We know most of the functionality, including wallet tracking and app locking will work for sure. At the very least, iOS backers will have access to these features.
We're trying to get the PIN lock and unlock available as an additional feature by the time we launch. While it's possible with a jail-broken phone, we prefer to not require our backers to jailbreak their phones.
We'll keep you updated in the next couple days!