1). If my phone worked, I wouldn't buy a new one.
2). If I had enough money, I'd buy a new phone.
3). I'd have enough money if I didin't spend so much on games.
4). I'd use mum's phone if it wasn't a smartphone.
5). If my phone worked, I'd call my friends.
Всё просто, главное запомнить правило образование предложений Second Conditional и немного попрактиковаться.