With their powerful processors and extensive connectivity, the best smartphones have become indispensable personal assistants. There are millions of phone apps and new ones debut all the time. we've hand-picked essential ones  for your convenience.

Health Apps

Calm

Simply put, Calm is your go-to app regarding guided meditations and sleep stories to reduce anxiety, increase mindfulness and develop gratitude. It's user interface is amazingly well designed and their scenes and sounds are of high quality. Calm is free to use and to download, however, you can always upgrade for a premium account later on.

Available on iOS and Android.

Flo Period & Ovulation

Flo is password-protected, so nosy friends, partners, or family won't know anything about your cycle unless you want them to. You can also sync your data with Apple's Health app and track your sleep duration, water consumption, and physical activity. For those trying to get pregnant, you can monitor basal temperature, test results, and see the tracker's estimate of your most fertile days.

Available on iOS and Android.

MyFitnessPal

By now, MyFitnessPal should be your go-to app regarding your health and fitness progress monitoring. With it you'll be able to track calories, monitor your progress, track your exercise routines and most importantly it offers you a data base of 3.2 Million different kinds of foods that you can select from to add to your daily caloric intake without having to enter it yourself, and best of all, it's free to use and to download.

Productivity Apps

Any.do (Android, iOS: Free)

Busy people often forget daily tasks and chores, but Any.do (Android, iOS) is there to keep your schedule on track with to-do list, reminders, notes and the ability to share lists with and assign tasks to others. The app lets you sync between phone, desktop, web, and tablet to keep your lists up to the minute. A voice-entry feature lets you add items to your task list just by speaking. Calendar integration is available for better task list management. Further enhance your productivity with cross-platform support for sub-tasks, notes, and file attachments. Choose either a free or premium version with advanced features.

Toggl (Android, iOS: Free)

Toggl (Android, iOS) is a free time tracking app available for desktop and mobile that makes time tracking a snap, whether for individuals or groups. Users can start, stop, and log times and tasks on their mobile phone or desktop with data syncing between the two platforms, allowing you to easily record hours spent on projects or tasks. Included tools help you organize, bulk edit, or tag entries for easy auditing and reporting, with the ability to import or export data in PDF or CSV formats. Premium subscriptions add features like locking time entries, reminders, rounding rules for billable time, as well as project and team management tools.

IFTT (Android, iOS: Free)

If you find yourself wasting a lot of time with repetitive internet tasks, or just want to automate tasks on your phone, try IFTTT (Android, iOS). The app comes with a variety of pre-built "applets" that automate tasks like backing up photos to cloud accounts, messaging your roommate or family if you're near the grocery, or having your smart lights turn themselves on when you return home from work. In addition to the pre-built applets, Users can also build custom tasks from these applets and services, combining multiple tasks and triggers in an "If This, Then That" structure (from which the app takes its name).

Audible

Audible is an audio app that allows you to listen to anything audio on your phone. It could be digital audio books, radio or TV programmes or audios on magazines and newspapers.
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