I can not seem to find an answer to this anywhere. My aim is to use a Mac, a PC, and an iPad for the CC Photography subscription (not yet purchased). But with only 2 GB of online storage my photo library will not fit. How is my photo library synced across all devices?
Moving this discussion to the Photoshop Lightroom forum.
Hygroman13 the community within in this forum are going to better be able to answer you question regarding how photos are synced within Photoshop Lightroom on the desktop and under iOS.
From the Lightroom Mobile FAQ:
Q: Does syncing images to Lightroom mobile use a portion of the cloud storage I get with my Creative Cloud membership?
A: No, the images synced to Lightroom mobile are not counted as a part of your cloud storage.
Lightroom mobile is currently tested up to 250,000 images - so you're more or less gated by how much your device can hold.