Theoretically, the app from your camera manufacturer is supposed to transform your mobile device into a versatile camera companion. In reality, most apps developed by camera makers are too limited and frustrating to be of practical use. Take SnapBridge from Nikon, for example. Geotagging, when it works, is slow at best. The file transfer functionality looks great on paper, but it supports JPEG files only. Worse yet, the app reduces the resolution of transferred photos to 2MP — most likely because transferring full-resolution JPEG or RAW files wirelessly would be excruciatingly slow. The app's only saving grace is the support for remote camera control (assuming you can even make it work reliably). But how often do you actually need this functionality? But if not the camera app, then what?
Apps-schmapps. Use a cable!
Let's start with the JPEG and RAW transfer first. No matter whether you're using an Android or iOS/iPadOS device, you don't even need an app for that — what you need is a cable. For current Android and iPadOS devices, a regular USB-C cable will do the job. For iOS devices with the Lightning port, an inexpensive Lightning-to-USB-A adapter is the solution.
Use the cable to connect the camera to your device, and offload the photos and RAW files using the system utilities of your device. Android features a dedicated file transfer utility, while the Photos app on iOS/iPadOS can take care of importing files from the camera. Better still, instead of connecting the device directly to the camera (which can be a bit cumbersome, especially when you're out and about), you can use a card reader. This approach is more reliable, much, much faster, and can handle both JPEG and RAW files. What's not to like?
Geotagging is good, geocorrelation is better
App-based geotagging is good, but geocorrelating is even better. Instead of relying on an app to provide geographical coordinates when needed, you can use whatever GPS tracking device or app to record your movements. You can then use a special tool to geotag JPEG and RAW files by correlating the time when each photo was taken with the position on the GPX track at that exact moment.
Although it may sound convoluted compared to app-based geotagging, it's actually not all that complicated. You only have to make sure that the clocks of the GPS tracking device and the camera are in sync and remember to enable GPS tracking before heading out. You can use practically any GPS tracking device or app, provided it can export data in the GPX format. Speaking of apps, while there are several GPS tracking apps available for Android and iOS, you can't go wrong with GPS for Android and Open GPX Tracker for iOS.
Before heading out, sync the smartphone's and camera's clocks, launch the tracking app or device, and off you go to photograph without worrying whether the photos are actually getting geotagged. When you're done, transfer the JPEG and RAW files from the camera to your machine, and export the recorded GPS data as a GPX file.
The final step is to geotag the photos by geocorrelating them with the GPX track. When it comes to geocorrelating tools, you're spoiled for choice. There are dedicated tools for all mainstream platforms (Geotagging Geotag Photos Pro, GeoTag, and KGeoTag, to name a few). And many popular photo management applications, like Adobe Lightroom and digiKam, can handle geocorrelation too.
See? You can do perfectly well without the clunky app for your camera. And there is a bonus, too. You can now turn Wi-Fi and Bluetooth in your camera off to increase the battery life.