Time was when only photography enthusiasts would edit their photos. Pretty much everyone else would merely copy the contents of their memory card to their PC and stop there, subjecting friends and relatives to mind-numbing slideshows full of duplicates and out-of-focus snaps.

These days, your most-used camera is probably built into your smartphone, with photos immediately saved to a 'camera roll' and maybe even automatically sent to your computer via the cloud.

It couldn't be easier to share these photos. You can email them, attach them to an instant message, or post them on Facebook or Twitter with just a couple of taps on the screen.

Instagram and other apps have proved surprisingly popular, but not all offer much in the way of precise control when editing your photos. They tend to be quick fixes, slapping on pre-defined filters (vintage being the most popular by far) and rounding off the corners to replicate those photo prints you'd get from Boots in the 70s.

When you want to go beyond this sort of 'editing' on a device with a touchscreen, there are plenty of apps to choose between, but one of our favourites is Snapseed, which is now owned by Google. Best of all, the app is free on the iPad, iPhone and on Android. On Windows and Mac OS it costs a few pounds.

Snapseed is nicer to use on a tablet than a smartphone thanks to the extra screen real estate, but it's equally easy on both types of device. As well as being able to apply vintage filters you can crop your image, straighten and rotate, apply auto corrections and selectively adjust areas. Is also includes fun effects such as centre focus, tilt-shift (for fake miniature photos) and a selection of frames.

There's control over each effect and adjustment, making it far more powerful than apps which only have pre-defined effects. You can change the strength of the effect, plus brightness, contrast, grain and much more.

How to edit photos using Snapseed

Step 1: When you launch Snapseed, tap the icon with a camera and a + symbol to open a photo. You can import from your photo library, the built-in camera or paste an image from the clipboard.

Snapseed iPad open image

Step 2: The available tools are shown on the left, with your photo on the right. Below the image are four handy buttons: Compare (tap it to show the original image with no edits), Revert (undo all changes), Save and Share (which we'll come to later).

Snapseed iPad tools

Step 3: Tap the Auto Correct tool. Your photo's contrast and colour will be optimised, but you can manually override the settings by tapping and holding on the photo. Swipe up and down to choose the adjustment, let go and swipe left or right to increase or decrease its value.

Snapseed ipad make adjustments

Step 4: Tap and hold Compare at the bottom to see the original image, and let go to see the edited version. When you're happy, tap the Apply arrow at the bottom right, or if you don't like the change, tap the Back arrow to exit the tool with no changes.

Snapseed ipad accept or reject changes

Step 5: Most tools work in the same way, and the Tune Image tool is likely the one you'll use most. It lets you adjust brightness, contrast, ambiance, saturation and white balance. With the latter, you'll see a handy guide at the bottom showing the various lighting types (though not the actual colour temperature).

Snapseed ipad adjust white balance photos

Step 6: You can sharpen photos using the Details tool. Typically, you'll want to activate the Loupe (magnifying glass) and drag it over your subject's eyes. Then you can swipe right to increase sharpness, looking at the magnified detail to ensure the correct level.

Snapseed ipad sharpen photos

Step 7: The Selective Adjust tool is one of the best as it lets you apply brightness, contrast and saturation corrections locally, rather than globally. Tap the Add button and place a marker somewhere on the image. Make and apply your adjustments as normal.

Snapseed ipad local adjustments

Step 8: Now you can have some fun and apply filters and borders. Tap Retrolux, for example. Swipe up and down to select from brightness, saturation, contrast, style strength, scratches and light leaks. Tap Style to display the presets, select one and tap Properties to customise it further.

Snapseed vintage filters frames photos

Step 9: When you've finished editing a photo, tap Save to create a new photo at the end of your Camera Roll. Then tap Share if you want to email it, post it to Facebook, print it or open it in another app.

 Snapseed save and share photos

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