QUICK SUMMARY
As part of its push to create "meaningful interactions" on its platform, Facebook announced on April 25 that new apps will no longer be able to publish posts to Facebook as the logged in user. In other words, you can't use an app to schedule out content and have it automatically post.
Apps created before April 25 that had been previously approved (like Buffer, CoSchedule, Hootsuite, Edgar, and others) can continue to post on your behalf until August 1, 2018.
After that, you'll no longer be able to use the apps to post content on behalf of personal Facebook profiles. This means that if you use a personal profile for your business, you'll need to post content manually and directly in Facebook.
However, you CAN still use these apps to post to business profiles and pages on both Facebook and Instagram.
WHAT TO DO
Check to make sure your business is using a business page on Facebook (and Instagram, if you use it).
If it's not, consider converting your personal profile into a business page. Here's how to do it >>
Be aware that while your friends and followers, photos and videos, and verified status will migrate over to the new business page, your posts and metrics will not.
Whether or not that's a worthwhile trade-off depends on how much engagement you currently get on your personal profile, how many posts there are (keeping in mind that very, very few people will ever see any of your old posts), and how often you schedule posts using third-party apps.
I know I'd be lost without Buffer and CoSchedule to help plan out posts for the upcoming weeks, but some people are perfectly happy using Facebook's native scheduling tool (scheduling with Facebook vs an app doesn't appear to make any significant difference to Reach).