What do you usually play using your smart phone? 

I usually watch youtube. -- I usually watch YouTube videos. => Another way: Your sentence is okay and this is another way of saying it.

​Oh,really?  ✔​

There are many home appliances.I bought a new computer. -->There were a lot of electronics. I bought a new computer.  => Corrected : The sentence is corrected grammatically.

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Congratulations  --> Congratulations! (Punctuation)

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