Background: Gamification is a promising approach to support rehabilitation, but implementing new devices after hand surgery (HS) faces challenges, especially in patient motivation and compliance. Technology-based, personalized solutions may encourage patients to perform gamified exercises consistently. This study investigated the impact of a tablet-based gamified hand-mobilization system on functional outcomes after HS compared to standard finger-expander training. Methods: Forty inpatients at BG Klinikum Duisburg were randomly assigned to a gamified or control group. Both groups underwent four weeks of stationary rehabilitation. Outcomes were assessed using the Disabilities of Arm, Shoulder, and Hand questionnaire (DASH), SF-36 health-related quality of life, and a visual analog scale (VAS) at pre- (T0) and post-training (T1). Tablet use frequency and duration were recorded. Results: DASH scores improved significantly over time (F(1.55, 58.85) = 16.36, p < 0.001, partial η² = 0.137) with no Group or Time × Group effects (p > 0.40), exceeding the MCID in both groups. SF-36 MCS, PCS, and VAS pain also improved over time (all p < 0.05) with no between-group differences (p > 0.40). Exercise duration differed (p = 0.007), but training frequency did not. Conclusions: Both gamified and conventional rehabilitation programs led to clinically meaningful improvements in hand function after hand surgery. No significant differences were observed between groups, indicating that the tablet-based system was feasible and well-accepted but not superior to standard training.