No one’s ready to admit that summer’s nearly over, but, as the days slowly get shorter and the back-to-school ads on TV get longer, it’s time to face facts: the first day of school is imminent. Whether you’re a college student making your way back to a demanding course schedule, or a parent ushering your kids back to a grade school routine, now is the time to start preparing.

Over summer, you might have experienced a common academic phenomenon – the summer slump. Detached from a formal educational setting for two months, your brain gets foggy, unable to retain new information as clearly. Sometimes, you even forget the concepts you learned last year, backsliding in your academic progression.

Thankfully, there’s an app for that. Many apps, in fact. Over the past decade, companies that create brain training programs that feature trivia, logic puzzles and interactive math problems have teamed up with app developers to create a handheld solution to the summer slump. Think of them as a gym of sorts – only, rather than working on your beach body in time for summer, you’re working on your brain in anticipation of the school year.

The best apps combine compelling cognitive games with smart, streamlined UX and sleek UI to create an accessible and engaging experience. The best mobile app development agencies, like Guarana Technologies (who developed the third entry on this list) understand the need for solidly-built code and attractive graphic design in brain training apps. If an app is going to whip your brain back into shape, it needs to be functional and appealing.

Below, you’ll find three apps that mix smart designs with challenging brain games.

Lumosity

Now the undisputed juggernaut in the world of brain training apps, Lumosity launched as a website way back in 2007. Developed by a neuroscientist from the Stanford School of Medicine, the initial aim was to take academic research about brain health and make an actionable platform for improvement.

While initially marketed as a way to reverse cognitive decline in sufferers of dementia and Alzheimer’s (creator Michael Scanlon was motivated by his family history with the latter disease), the company has since walked back on that angle. With more than 85 million users, they now focus on spreading research-based brain training to a broad community.

Lumosity is run on a subscription model ($15/month at the time of writing), so it’s certainly not the cheapest option on this list. But it’s nearly unmatched in its breadth of content and user-friendliness.

Mensa Brain Training

The quintessential “thinking person’s” society was late to adopt mobile apps, launching in 2015. But what they lack in finger-on-the-pulse relevance, they make up for with their cache of diverse and engaging exercises. To help you achieve a comprehensive brain workout, the Mensa Brain Training app breaks its training down into five disciplines:

• Memory
• Perception
• Reasoning
• Agility
• and Concentration

A well-rounded contender, it’s perfect for combating the summer slump. Sure, the user interface could use a design facelift, and the app designers are sluggish with updates, but, unlike Lumosity above, the app is free of charge (with required registration and in-app purchases.)

Quiz Run

What sets Quiz Run apart from the other two entries on this list is its multiplayer functionality. There is a wealth of research to indicate that learning with others has unique advantages over learning alone. That’s not to say solitary learning doesn’t have its place, but it doesn’t provide the same collaborative and competitive elements as group learning.

In Quiz Run, launched in 2015 for iOS, you square off against friends to see who can answer trivia questions the fastest. With a loose narrative surrounding a race, the objective is to best your best friends in an ongoing trial of mental dominance.

As the name suggests, Quiz run is more trivia-focused than the other apps here, which tend to take a holistic cognitive approach to brain training. But for its cheery interface, addicting format and crisp usability, it’s a valuable tool in your back-to-school, brain-strengthening arsenal. Plus, it’s free!