Objective: The aim of this randomized controlled trial was to assess the effect of the smartphone application-based reminders on plaque scores in orthodontic patients. Methods: 60 patients aged 12-30 years undergoing orthodontic treatment were randomly allocated to two groups (30 each). Control group which received standard oral hygiene instructions and experimental groups which received standard oral hygiene instructions along with smart phone application-based reminders twice a day. Plaque scores were assessed by using Turesky modified Quigley-Hein plaque index (TMQHPI) at three time points, baseline (T0), after 2 weeks (T1) and after 6 weeks (T2) of screening. Results: Both experimental and control group exhibited comparable plaque scores and baseline statistics. No significant difference was found at T1 (control: 16.2±4.3, experimental: 14.9±4.9, p-value: 0.29). Significant reduction in plaque scores was found at T2 (control: 16.3±5.2, experimental: 12.2±6.1, p-value: 00007). Conclusions: Smartphone application-based reminder therapy for oral hygiene maintenance during fixed appliance orthodontic treatment decreases the plaque scores at 6 weeks.