This randomized controlled trial tries to find out the effect of mobile phone-based text message reminders on time to drop out from treatment among patients with severe mental illnesses after discharge from an inpatient setting across a follow-up period of 12 months from discharge. The patients will be randomly divided into two groups (intervention and standard care groups). The intervention group will receive two sets of text message reminders on their mobile phones. One set will be variable one, where they will receive a text message on the phone three days and five days before their next follow-up visit (every four weeks). The second set of fixed-frequency text message reminders will be sent for medication adherence on Monday and Thursday of every week. There will be twice weekly messages except in one week, with four messages per week. The control group will get the usual treatment during the study period (12 months) without any intervention. Both groups of patients will be assessed for time to drop out across a 12-month follow-up period and for change in medication adherence, insight and functioning at baseline, at eight weeks, six months.