My smartphone is with me at all times. Mainly, it's how I communicate with family and friends via text, email, social media, and yes, occasionally by voice call or video call. Though voice is probably the least-used method of communicating lately. Our kids and grandkids are all nearby and we all coordinate activities every day using our phones.
The second most used feature is the camera. DW and I take pictures and video every day (grandkids, projects, activities), which are automatically uploaded to both Google and Amazon so we can view them on the TV at the end of the day. We also like the sharing capability and search function using facial recognition, location, and other features.
Third most useful capability is GPS navigation with real-time traffic updates, POIs, and other features. I turn it on even when I know exactly where I'm going because both Waze and Google Maps do an excellent job of getting you around slowdowns.
It's also a necessity for Uber and Lyft, which we are using more and more when we travel. I use Pandora and Tidal for music and I also listen to podcasts while working in the shop. It's necessary to monitor our Wyze security cam. We use it for boarding airplanes and getting into sports/performance venues whenever possible. Also using it more for picking up purchases using lockers at Home Depot, Wal-Mart, etc. It's pretty much a necessity when traveling to get real-time flight status updates, gate changes, etc. It's also needed for 2FA authentication at Fidelity using VIP Access. Also keep my password application on the phone so my complex passwords are always accessible. And when I'm waiting in line somewhere or otherwise have some downtime, it's convenient to catch-up on news, weather, social media, or just play a video game.
Without my smartphone, I would be lost in space. I suppose it's easy to say I don't need all that stuff... until the gate changes on your flight twice while you're grabbing some lunch between flights. That happened to us last Sept. I like keeping up with technology in general, but smartphones in particular have made me more productive and enhanced my life in more ways than I could possibly list here.