Fix Blurry Instagram Uploads

I have high-resolution photos that look razor-sharp on my computer, but once they arrive on my iPhone via AirDrop and I try to post them to Instagram they lose clarity and appear noticeably soft. I need a clear, repeatable workflow that lets me publish these same images at the maximum quality Instagram allows—no blur, no strange compression artifacts.

You’ll need to
• diagnose what happens between AirDrop, the iOS Photos app, and Instagram’s compression pipeline,
• show me the exact export or resize settings (Lightroom Mobile, Photoshop, or any equivalent) that preserve sharpness while respecting Instagram’s 1080-pixel width limit, and
• walk me through the correct in-app posting steps or third-party tools to keep Instagram from down-sampling the files.

Acceptance is simple: when I follow your steps on my iPhone, the photos must appear as crisp on my Instagram feed as they do in the Photos app before upload. Provide a concise guide I can reference for every future shoot.