Don't do this
They want access to accounts on your device meaning Facebook, Twitter , etc.
Access to phone calls and contacts
Modify or delete content saved to your SD cards
That's interesting. I wonder what they would want with that information.
Hm, reading my post above, I realize that I sound like a bot and that would sound suspicious to anyone! Please do not be alarmed, I am human and made of skin and flesh and whatnot. But to each their own to anyone who does or does not decide to download the app. ☮
@Ms.Virgo a bunch of apps ask for that kind of permission. Access to accounts = so you can log in with facebook or google+, phone calls and contacts = so you can get notifications. Modify/delete content saved to your sd card = so if the app updates they can store memory into the sd card. All of these are basic things that a bunch of apps already do but they can't do it unless you give them all those extreme permissions. It's more an android thing than a suspicious app.
Then you're in luck! You can get 10 coins through downloading the Lezhin-plus app. I'll link instructions. If you're invested in RS like me then only being able to purchase 3 chapters for the time being shouldn't be a problem since it's the only new chapter available right now.
http://aminoapps.com/page/anime/4174825/getting-10-free-coins-on-lezhin