Supporting older operating systems seems like a user-friendly choice, but it creates hidden costs. Developers face slower feature development, as they must write conditional code paths and avoid new APIs. This leads to a lowest common denominator approach, limiting innovation and tying teams to outdated platform capabilities.

Testing complexity multiplies with each additional OS version. Manual matrices grow, and automated tests become harder to maintain. Bugs often surface only on older systems, making them difficult to reproduce. Designers also hit limitations, forced to simplify interactions and postpone modern UX improvements for consistency.

The business impact is clear: increased development time, QA costs, and release risk, often masked as slower velocity. Meanwhile, users on old versions upgrade less and report more crashes. To choose a realistic minimum, teams should analyze user distribution, align with platform support, and consider their app category and feature roadmap.