There are many great language learning apps that are either free or have low cost options. Some of the most popular ones are:

Duolingo - A free app that offers bite-sized lessons in over 20 languages.
Babbel - An app that offers courses in various languages for a fee, with a free trial available.
Anki - A spaced repetition app that can be used for language learning, available for free on most platforms.
Memrise - A free app that uses a combination of memory techniques and gamification to help with language learning.
HelloTalk - A free app that connects you with native speakers for language exchange.
These are just a few examples, but there are many other great language learning apps available, so it may be worth trying a few to see what works best for you.
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