1. Google
2. ICloud
3. One Drive
Feature | Dropbox | Google Drive | Microsoft OneDrive
------------------------------------|----------------------------------------|------------------------------------|---------------------------------
LAN Sync | ✅ Yes (fast, LAN-based) | ❌ No | ❌ No
Block-Level Sync (Delta) | ✅ Yes (all file types) | ❌ No (reuploads entire files) | ✅ Yes (only Office file types)
Smart Sync (Cloud stubs) | ✅ Yes | ❌ No | ✅ Yes (Files On‑Demand)
Selective Sync | ✅ Yes | ✅ Yes | ✅ Yes
Version History | ✅ 30 d (Free), 180 d (Plus), **365 d with Extended add‑on** | ⚠️ 30 d (Free), 100 versions per file (Docs/Sheets/Slides) | ⚠️ 30 d (Free), up to ~500 versions (Business)—based on version count, not time
File Requests (External U/L) | ✅ Yes (no login needed) | ⚠️ Only via Forms workaround | ⚠️ Business accounts only
Office Integration | ✅ Supported via Office Online | ✅ Google Workspace ecosystem | ✅ Native Office integration
Google Docs Integration | ❌ No | ✅ Yes | ⚠️ View only
Offline Access | ✅ Smart/Selective Sync | ✅ Manual via app settings | ✅ Files On‑Demand
Collaboration Tool | ✅ Dropbox Paper | ✅ Docs / Sheets / Slides | ✅ Word / Excel Online
Ecosystem Independence | ✅ Fully independent | ❌ Tied to Google Workspace | ❌ Tied to Microsoft 365
3rd‑Party Integration | ✅ Broad, vendor‑neutral | ✅ Google‑centric | ✅ Microsoft‑centric