But it is still possible to get some fairly compact handsets and the Nokia Lumia 620 is one such phone.
With a screen of just 3.8 inches this thing is pretty small. Its full dimensions, if you're wondering, are 115.4 x 61.1 x 11mm, so while it's not the slimmest phone around it's quite compact overall.
At just 127g it's also pretty light and while it's a budget handset it's no slouch as a smartphone either. Its 1 GHz dual-core Snapdragon S4 processor and 512MB of RAM may not sound too impressive but they serve it well and Windows Phone 8 is far from resource hungry at the worst of times.
Also consider: Samsung Galaxy S4 Mini
The Samsung Galaxy S4 Mini isn't quite as small as the name might suggest. In fact with a screen size of 4.3 inches you might be surprised to see it listed in this category at all. But its dimensions of 124.6 x 61.3 x 8.9mm mean that while it's quite long it's also slim and not particularly wide.
When it comes to weight the Samsung Galaxy S4 Mini fares even better as it's just 107g, which means it's so light you're likely to forget you're carrying it, which is excellent when you don't want to give up any extra grams when jogging.
Fitness credentials aside it's also a decent handset, with a 1.7 GHz dual-core processor and 1.5GB of RAM.
Best phone for fitness accessories: iPhone 5S
While a smartphone can be a great tool for getting fit you may find that you want other accessories to supplement it. They may take the form of a dedicated fitness tracker like the Fitbit Force, an armband to hold your phone in place while jogging or anything in between.
The problem is that not all fitness accessories are compatible with all phones, but thanks to its immense popularity there are a large number of accessories that are compatible with the iPhone 5S, including big name things like the Nike Fuelband SE, which is currently only compatible with iOS devices.
Also consider: iPhone 5C
Yes it's another iOS device, but an iPhone really is the best option for fitness accessories, and this is a cheaper option for fitness fanatics on more of a budget.
Due to differences in the design the iPhone 5C won't necessarily be compatible with all the same accessories as the iPhone 5S, but there is a lot of crossover.
Some popular Android phones such as the Samsung Galaxy S4 come close, but they still can't quite match the selection available to Apple's handsets.
- You've got the phone now get the apps with our guide to the 10 best fitness apps for Android.