Based on strategic group theory, this study investigates the relationships between app developing choices, firms’ strategic characteristics and firm performance. The sample contains Chinese internet firms whose mobile apps were in operation in the sample period. This study finds that: (1) Firms with large business sizes or wide scopes of mobile internet business are more likely to benefit from developing the second most important apps. (2) Firms with small business sizes or narrow scopes of mobile internet business are more likely to benefit from developing the most important apps. (3) If a firm has both a large business size and a wide scope, the interaction between the characteristics increases the benefit from developing the second most important app. (4) If a firm has both a small business size and a narrow scope, the interaction between the characteristics increases the benefit from developing the most important app. These findings indicate that the strategic characteristics can interact with each other and form meaningful strategic types. The dimensions shaping strategic groups should be understood in a combined rather than separate way.