a second phone? how to describe the phone that's not your daily driver?
I have two phones that I use pretty much everyday. My daily driver is my new iPhone 8p. And also I have an iPhone 5, which I use everyday but not as frequent as iPhone 8p. So, can I describe my iPhone 5 as my "standby phone", "backup phone" or simply my "second phone"? We use "备机“ in Chinese, which literally means " backup phone". Thank you.