If you want to keep growing, you should never stop learning. These websites and apps help you learn new skills with the right online courses. You can also tap them to find study partners for that classroom feeling.

Many universities and schools make their coursework available for free online, in what is called Massive Open Online Courses (MOOC). You can go for paid courses too that offer legitimate degrees once you finish them.

Finding the right course for your time availability and budget, and completing it within the timeframe, is the difficult part. So here are a few ways to make that search easier.

1. Coursesity (Web): Directory of Online Courses Across Subjects

If you're looking for a list of different online courses about a subject or topic, head to Coursesity. The directory lists over 50,000 online courses from a variety of platforms, across subjects like programming, arts, office productivity, science, etc.

Pick a subject to see all the courses available in it. You can then filter the results by user rating, duration, price, language, certificate availability, and difficulty level. These filters are key to discovering the right course for you. Once you find it, add it to your collection.

Collections are an integral part of discovering courses on Coursesity. The founder, Keyul Shah, has a list of recommended courses in collections on different subjects, but you can also see any user's collection for inspiration.

Collections like the Free Ivy League Courses help in narrowing choices and discovering authorized content you wouldn't easily find otherwise.

2. Online Course Report (Web): Course Rankings for Part-Time Students

Merrill Cook is curating online courses like a lot of other websites, but with a different focus. Online Course Report (OCR) recognizes that online learning is more popular with non-traditional students and adult learners. It's often taken up by someone who has a full-time job, or is looking to add a skill set to their daily responsibilities.

OCR creates course rankings that put an emphasis on flexibility and affordability, which are two of the most important aspects for online learners. Visit the Rankings page to see links to the top 10 or top 50 rankings for different topics. Each article details why the ranks were chosen, hourly rates and eventual salary, graduation rate, and other important criteria to help you make a decision.

The website also has a floating "Find Your Degree" panel that's always visible, but you can ignore it. It's an ad that takes you to a different website, so don't bother using it.

3. Prodeus (Chrome): Free YouTube Online Courses Search and Tracking

YouTube has a vast library of free video courses to learn a variety of skills and subjects. Prodeus wants to help you earn a virtual degree on YouTube by searching for free online learning courses, and tracking your hours and classes.

You can find classes on YouTube through Prodeus in the dropdown pane when you click the Chrome extension icon. The library will show different courses uploaded to the video sharing site, which you can filter by newest, popular, or recommended for you.

You can sort by category, difficulty, and language. You can also switch between regular classes and full-fledged courses. Each course also shows a rating.

Once you've selected a course, Prodeus will track your progress in it. The extension watches how many hours you use YouTube for learning, which it converts into virtual "ProDegrees" based on the number of class hours, the number of classes, and "credits" you earn.

There's a bit of gamification too, as you unlock stages based on the total number of class hours. In the end, you might just get a Master's degree by learning on YouTube.

Download: Prodeus for Chrome (Free)

4. Knowable (Android, iOS): Podcast or Audio Online Learning Courses

While most online courses feature a series of videos, that's not every student's preferred learning style or every expert's favorite teaching style. Knowable focuses on audio-based online learning courses, so you can listen to them like a podcast when you're working out, driving, or running chores around the house.

You'll find a variety of courses, like startup and entrepreneurship advice, self-improvement and personal development, health, business, and more. There are a handful of free courses too, so you can try out what it's like to learn through listening alone. But most of those by experts or well-known names are paid courses, each with a different price.

As with most online courses, you can preview an index of what the tutor will cover. A lot of the courses offer a free invitation for a friend, so two people can learn for the price of one. Having a study buddy is also a great way to stay motivated with online learning.

Download: Knowable for Android | iOS (Free)

5. Cuddy (Web): Find a Buddy to Take Courses Together

School is more fun when you've got a friend to lean on. You can share notes, discuss what you learned, and even compete with each other. Cuddy wants to help you find a buddy for any online course you're taking.

Click "Find a Buddy" to see listings of people looking for different types of partners. Some have specific course requirements, while others are interested in a general study partner regardless of the subject. You'll find details like the type, the skill level, a course link, and a general description.

You can add your own listing if who you seek is not already on Cuddy. Be as clear as you can about the course name and type. And focus on the details or description, where you talk about yourself. This is what Cuddy users will look at and try to figure out if they want to be your study buddy. Talk about your learning style, objectives you want to achieve, and what you're looking for from a buddy. It'll lead to the best match.

Search Engines for MOOCs

The websites in this article feature a mix of paid and free courses, so you can get full-fledged university degrees or rely on expert advice. But before you do that, you should check out the number of free online courses too, which can offer a great education at no cost.

It can be difficult to research only about these free courses, but there are some options. Start with the best sites to search and find MOOCs, which also include free guides for degree paths.