Mobile apps are one of the best tools you can use when it comes to keeping New Year's resolutions. Why? Apps are always with us. They can remind us at specific times or places of what it is we want to do. And considering how many times a day the typical smartphone user looks at her screen, just seeing an app icon can serve as a gentle nudge in the right direction.What is it you hope to do, achieve, or become in 2016? Last year, the most popular New Year's resolutions , according to Nielsen, were staying fit and being healthy, followed by losing weight. The next most popular ones were enjoying life to the fullest, spending less money, and saving more. For many, enjoying more quality time with family and friends was another top priority.Some of those goals might sound a little too metaphysical to tackle with a mobile app. But keep in mind, an app is just a tool that coaches you along, provides helpful reminders, or finds other ways to keep you motivated — such as through rewards or gamification.If you're looking to make, and actually keep, your resolutions this year, click ahead for seven options you should check out.