Mobile phone ownership, usage and readiness to use by patients in drug treatment.

•We surveyed 389 substance abuse patients about their mobile phone use, preferences and ownership.•Eighty-three percent owned a mobile phone, 57% had smartphones while 72% had pay-as-you-go contracts.•Fourty-six percent changed their mobile number in the past year, 15% >three times.•Fourty-six percent thought the use of geo-location to be unacceptable.•Mobile phones are widely available among SUD patients and are an acceptable method of contact for stable patients.•Issues remain around smartphone ownership, data allowances and use of geo-location tracking functions.