which things must i have learn to be a app developer for mobile phones and which code i have to know ?​

C

Explanation:

read c programming perfectly

ιт ιѕ ωнєи ѕσмєσиє ρυтѕ ιи α ¢σ∂є σя ѕσмєтнιиg тнαт вяιиgѕ α νιяυѕ, σя мєѕѕєѕ уσυя gαмє υρ, σя αℓℓσωѕ тнєм тσ ¢нєαт.

αи∂ уєѕ ι нανє вєєи нα¢кє∂ вєfσяє(ιт αιит fυи)

нσρє ι ¢συℓ∂ нєℓρ уσυ.

professionals can use many types of technology that can them. some examples are, computers (they research and can use for programs for data, they are also used for job applications, school work, and even to make new ideas), speedometers (can get data for unknown data), sometimes something as small as a pen (used for rough drafts, to insert data, and again job applications).