It may not be a long wait for an iPhone with built-in satellite communication to become available. According to 9to5Mac, well-known analyst Ming-Chi Kuo claims that the next iPhone (possibly called the iPhone 13) will include support for satellite calling and messaging in low Earth orbit.
I would be able to get in touch at a remote campground with no cell service coverage and without buying a separate satellite communicator.
The iPhone would supposedly use a modified version of Qualcomm's X60 modem to communicate with satellites. It's not certain if satellite support would be limited to certain apps, though we wouldn't be surprised if that were the case. Mobile satellite service is usually much slower than conventional cellular data, ruling out many of the internet-intensive apps for people.
However, there are good reasons to be skeptical. A 2019 Bloomberg rumor said Apple was developing satellite technology for the iPhone, but the team expected to release a product in five years - two years may be too soon, assuming the leaks were accurate in the first place. There are also logistical issues to address, such as the choice of service providers. Satellite service has historically been expensive and can be a hard sell, even if you regularly venture beyond cellular coverage.
Many expect Apple to launch the new iPhone lineup in September. It is uncertain whether this would be limited to Pro models or cover the entire iPhone range.
If there is a satellite link, however, Apple may have a stronger hook for the new iPhone than rumored screen and camera upgrades. This would be the first popular smartphone to offer connectivity virtually anywhere on the planet, and competitors may not match the feature for a while.