Jessie J "doesn't like" taking phone calls.
The 'Domino' singer - who recently split from Channing Tatum - would prefer to receive a text or a voicemail because she worries about having microwaves so close to her brain.
She said: "I turn my phone on airplane mode [in the evenings]. I don't like calls. Send me a voicemail. Text me.
"I don't like having my phone on one ear, microwaves can f**k off."
The 31-year-old star likes to take time to herself and properly unwind in the evenings.
She told Britain's Grazia magazine: "I go through my house and make sure that everything's good.
"I like to go to sleep knowing that the washing-up is done and the laundry is hung out.
"Then I'll put some music on. I like chilled music, like Sade or Tracy Chapman.
"And I'll always light candles and have a bath.
"A friend of mine came over the other day and she was so stressed, so I said, 'I'm going to do for you what I do for myself', and I ran her a bath.
"I like to wash the day off me, you know?
"If someone's had bad energy, it's all scrubs and pink salt all over me."
While Jessie divides her time between the UK and the US, her heart will always lie in London.
She said: "Home is everywhere because I'm always on the road.
"But I have a place in London and a place in LA.
"My heart is in London but my stuff is in LA. When I wake up, I'm like, 'Where am I?' "