John Mayer still follows his ex-girlfriend Katy Perry's life.

The 40-year-old singer and songwriter dated the 'Roar' hitmaker on and off for two years from 2012, and he has admitted five years down the line he still checks in on his former flame, and even tuned into her four-day YouTube video, which was to promote her fifth album 'Witness', and he even watched her sleep, although he has acknowledged the footage made him feel weird.

Asked if he tuned into the live stream on 'Watch What Happens Live with Andy Cohen' on Monday (27.11.17), he said: ''Yeah, I did. I think you'd have to watch all 96 hours to get the final verdict. That's her thing, man - to go big and bold. Yeah, I checked in with it. It's definitely odd to watch your ex-girlfriend asleep.''

But the 'Your Body is a Wonderland' hitmaker has no qualms about admitting to tuning in to the footage, and he has even encouraged people to admit to their actions.

He added: ''The way I see things now, I call it 'stand in the middle of the boat.' If someone says, 'I don't watch that,' it's like, 'Yes, you do.' You know? Watch when you want to watch it. Be human about it.''

And while John was honestly opening up about his activities, he also revealed he texted the 33-year-old artist to wish her Happy Birthday last month.

He said: ''It's like, if you want to text someone ... I texted Katy happy birthday. It was four in the morning. It was like a post-midnight, haven't-gone-to-sleep-yet, it's-technically-your-birthday send. Because how weird is it to be like, 'I want to say happy birthday now, but I'm going to wait until tomorrow afternoon?'. Be a person, man.''

Although Katy has hailed John as the greatest lover out of all the men she has been romantically linked to, including ex-husband Russell Brand and Orlando Bloom, the 'Gravity' rocker has not reciprocated the complement, but agrees with the 'Swish Swish' artist.

He said: ''Right here [pointing to his head]. So far, it's on a little SD card, I've been creating it myself. I've been my best lover so far.''