There are higher quality earphones and earbuds you can buy for use with your iPhone, iPad, and iPod touch. However, Apple's own EarPods are ubiquitous as they come with every iDevice.
The problem with EarPods is keeping 'em in your ear. After extended use, even if you're relatively still, they tend to slowly wiggle out. However, when you're running, hiking, biking, walking, etc., they pop out quicker and more often.
A simple solution is the inexpensive Sprng clips (yes, that's spelled correctly). You simply snap the Sprng onto your Apple EarPods, then slide the clip up or for a "custom" fit. Voila! Your earbuds stay comfortably in place. (Note that your your ears may not be exactly the same so each side may need to be adjusted slightly differently.)
The Sprng clip is available in pink and grey. They work with the EarPods that came with the iPhone 5/5c/5s, iPod nano (seventh generation), and iPod touch (fifth generation or later). Sprng clips cost US$10 for one set — or you can get four for $30.