Why do the colours of my images look different from iMac to iPhone?

Hi there 

I recently bought a new iMac and after exporting my photos from lightroom and transferring them onto my iPhone the colours look different. The black and white images have a blueish tone and the coloured images look a bit dull with a slight green tone. I've never had this issue before! I'm exporting the photos out of lightroom using jpeg format, colour space sRGB. 

Any ideas on how I can resolve this issue would be greatly appreciated!