Stars are basically duplicate stickers in your collection and they are used to open vaults in the album tab. Different stickers have different star values, according to the number of stars that each sticker is. There are usually three vaults that can be opened in Monopoly Go:
The Pink Vault is the best one to get and it's definitely worth saving up the stars or getting friends to send you stars in order to get one. Here's everything you need to know about how to send stars in Monopoly Go.
If you know someone that needs some stars in order to get enough stars to open a vault, send them some stars, here's how:
Remember though you can only send five stickers per day, so if the goal is to send as many stickers as possible, then send your stickers which have more stars.
You may also want to send yourself stickers, to do this you'll need to create a second account in the game. Probably using another device, and with different social account details. If you have a second or 'alt' account you can then use it to feed extra stars to your main account.
Then the process is the same as above, be friends with your alt account and then just select and send stickers as detailed above.
The number of stars you get for each sticker depends on the star level of the sticker that you send. 1-star stickers will send one star, 2-star stickers will send two stars etc...
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