The number of people who use a digital camera for their snapshots is steadily declining, but that doesn't mean there still isn't a market. If you have a camera that doesn't automatically geo-tag your photos, you can do so manually with Apple's Photos app.

Normally, when you take a picture on your smartphone, be it an iPhone or Android device, it will usually tag your photo with your location. It's actually very precise, too, which is why many choose to disable geotagging, and remove any personal information before uploading photos to the Internet.

Related: What Is EXIF Data, and How Can I Remove It From My Photos?

In the following photo, a delicious smooothie-to-be is tagged with its location. To see this information in Apple's Photos app on the Mac, first select a photo and then use Command+I to pull up its metadata, which includes the name of the image, date, size (dimensions and file), and much more. You can also add a description, faces, and more.

Down at the bottom is the location data.

Here's another photo used with a "dumb" digital camera. Because this camera has no GPS capabilities, it didn't tag the photo with any location data. We can assign a location if we want, however, by clicking on "Assign a Location" at the bottom.

It's not necessary to type in the whole name. You can simply type a few letters or the first word, which will let you choose from a dropdown list.

Once you've settled on a place (it won't be pinpoint accurate unless you know the exact address), then you can hit "Enter" and it will automatically be saved to your photo.

This is great, but what if you want to tag multiple photos? After all, it's doubtful you went on vacation and only took a handful of shots. You probably snapped hundreds.

It's as easy as you'd imagine. First select your group of photos. You can click and drag to "lasso" a group, use the Command key to select multiple photos, or use the Shift key to choose a range.

As you can see in our info panel, we've selected three photos. We can now add pertinent information such as a title (vacation, business trip, or something more descriptive), keywords, and of course, location.

Again, in the "Assign a Location" section, we just need to type a few letters of the location name and choices will appear in a dropdown list. Since we've selected multiple photos, we'll add the location information to all of them rather than having to do each one at a time.

As of now, you can only add geo-tag information to Photos on OS X, so if you try to do it on Photos for iOS, you won't be able to edit the metadata at all, let alone the location information.

An app called GeoTagr will do the trick on iOS, but since your iPhone or iPad already geo-tags photos by default, you may not be super anxious to tag all your dumb camera photos since it's so much easier to do so on your Mac.