Background: Prolong usage of smartphone leads to musculoskeletal disorders such as upper cross syndrome or otherwise called as forward head posture or text neck. Prolonged improper posture leads to increased load on the cervical muscles and joints which leads to reduction of cervical muscle strength followed by weakening of respiratory muscles and alters the expansion of thoracic spine during inspiration and to rest during exhalation. Materials and methods: 50 participants were selected and they were divided into two groups (Group A, Group B) each group consisted of 25 participants. Lung functions (Forced vital capacity and forced expiratory volume in one second of both groups (Group A, Group B) were measured using spirometer (pre test and post tests). Conclusion: Group–A (stretching) has improved significantly than Group–B (controlled breathing exercise).so it is concluded statistically that group–A (stretching) improved respiratory functions among smartphone using collegiate.