Our smartphones can detect how many steps we have taken in a day, where we are walking to,and what the weather will be like this weekend.
And now, a childhood cancer charity has said the camera on our phones is also capable of detecting a type of eye cancer in children under five.
The Childhood Eye Cancer Trust (CHECT) has highlighted how the flash detects retinoblastoma (Rb), a type of cancer where tumours develop in the eyes of babies and young children.
This cancer can destroy their vision and threaten their life, although symptoms of it are very subtle.
When a tumour grows inside a child's eye, it can reflect back as a white pupil in flash photos and if spotted early, it could save a child's vision, eyes and life.
CHECT said that with the average person spending hours of their life staring at their phone screen, they should put the devices to better use by using them to look for Rb.
Eilise Somers noticed that one of her four-month-old daughter Arwen's eyes appeared white when she took a photo of her on her smartphone last year.
She was referred to a specialist, who confirmed she had Rb.
Ms Somers, from Harmston, Lincolnshire, said: "She confirmed there was a growth in Arwen's left eye and made an appointment three days later at Birmingham Children's Hospital where the definitive diagnosis of retinoblastoma, grade D+ was made.
"At this stage we found ourselves making the heart-breaking decision to have the affected eye removed."
Since the operation to remove her eye, Arwen has made a full recovery and has just celebrated her first birthday.
The campaign is being launched as part of World Retinoblastoma Awareness Week.
"Our hope is that our research will mean no child ever has to experience the trauma of losing their eye, their sight, or their life through eye cancer," said CHECT chief executive, Joy Felgate.
"Retinoblastoma is one of the most devastating illnesses children and families can face. Many children have to endure the loss of an eye followed by aggressive bouts of chemotherapy, years of examinations under a general anaesthetic and prosthetic eye care - which, as you can imagine, is particularly traumatic for a toddler."
Almost one child under the age of five will be diagnosed with Rb every week in the UK. It is very treatable and 98% of children will survive, but most will need to have an eye removed.
Apart from a white appearance in flash photography, other signs include:
- A newly onset squint
- A change in the colour of the iris
- Soreness or swelling in the eye without sign of infection