A 720p file typically ranges from 800MB to 1.5GB, making it easy to store on a smartphone or a small flash drive.
On screens smaller than 10 inches, the difference between 720p and higher resolutions is almost indistinguishable. About the Movie: Cowboys & Aliens (2011)
If you want to skip the risks of torrenting, Cowboys & Aliens is widely available on legitimate platforms that offer "Offline Viewing" (the official version of a portable download):
Depending on your region, the film frequently rotates onto these streaming services, which offer a download feature within their mobile apps.
If your movie download ends in .exe or .zip instead of .mp4 or .mkv , delete it immediately—it’s likely malware. Legal Alternatives for Portable Viewing