A bokeh effect is a photography trick used by many to change the context and presentation of a picture. The name derives from the Japanese word boke-aji, which directly translates to 'blur-quality'. The effect blurs a certain part of the image and adds lens flare effects to your image.
The bokeh effect originally comes from the lens, where you need a lens that can change focus, such as is the case with the iPhone 7 and iPhone 7 Plus, however the same effect can be recreated (through software) on any iPhone - if you're interested about the photography trick, check Nikon's website for a detailed explanation.
How to get bokeh effect without iPhone 7: Camera apps
The depth of field is one of the most important tweaks you're going to have to tweak, and this can be achieved through certain apps (or through the iPhone 7-line). In Camera+ you will be able to change the depth of field of your images by editing it as you're taking it; granted these images won't look as good as a lens that uses hardware to create a different depth of field, but we are happy with the results.
Once you've played around with the depth of field, which essentially adjusts the focus on the image, you can edit the image to create a bokeh effect. Also see: iPhone 7 vs iPhone 6s comparison review.
How to get bokeh effect without iPhone 7: Add bokeh effect to images
These apps will provide you with a huge amount of customisation and very easy way of editing your photos. The process is very simple and the way you customise the image entirely depends on what you're trying to achieve.
Once you've added the effect, you can use other apps to further edit the images you've taken, such as Afterlight (£0.79), Snapseed (free) and Lightroom (free). The quality of your edits will of course depend on the original image you took and more so with the camera it was taken with - the newer the iPhone, the better the image will be (due to general better hardware in later iPhones).
After you've finished editing, feel free to share it on social media, set it as your iPhone wallpaper or use it to show off your new found photography skills to your friends.
Also see: iPhone 7 vs Samsung Galaxy S7 comparison.