create-farcaster-mini-app/src/lib/devices.ts

function isAndroid(): boolean {
  return (
    typeof navigator !== 'undefined' && /android/i.test(navigator.userAgent)
  );
}

function isSmallIOS(): boolean {
  return (
    typeof navigator !== 'undefined' && /iPhone|iPod/.test(navigator.userAgent)
  );
}

function isLargeIOS(): boolean {
  return (
    typeof navigator !== 'undefined' &&
    (/iPad/.test(navigator.userAgent) ||
      (navigator.platform === 'MacIntel' && navigator.maxTouchPoints > 1))
  );
}

function isIOS(): boolean {
  return isSmallIOS() || isLargeIOS();
}

export function isMobile(): boolean {
  return isAndroid() || isIOS();
}