Comet is the better app overall, scoring 8.2 to 7.9. Comet wins on 4 of the 5 scores, Grok on 1.
Researchers and heavy web users who want AI help beside every tab
X users and news followers who want fast takes on what is happening right now
Score by score
The details
| Feature | Comet | Grok |
|---|---|---|
| Category | AI Assistants | AI Assistants |
| Category rank | #10 of 16 | #15 of 16 |
| Developer | Perplexity AI | SpaceXSI (formerly xAI) |
| Pricing | Free + paid plans | Free + paid plans |
| Usable for free | Yes | Yes |
| iPhone & iPad | ✓ | ✓ |
| Android | ✓ | ✓ |
| Mac | ✓ | — |
| Windows | ✓ | — |
| Web | — | ✓ |
Common questions
Is Comet better than Grok?
Comet is the better app overall, scoring 8.2 to 7.9. Comet wins on 4 of the 5 scores, Grok on 1.
Which is cheaper, Comet or Grok?
Comet: Free on every platform; Perplexity Pro ($20 a month) and Max raise the limits. Grok: Free tier; SuperGrok plans from $10, with higher tiers for heavy use. On value for money, Comet scores higher.
Do Comet and Grok work on the same devices?
Only Comet runs on Mac, Windows. Only Grok runs on Web.
Which is more private, Comet or Grok?
Comet scores higher on privacy (5.8/10). Perplexity says Comet keeps browsing data on your device, but with a synced account it may record your history and use data to improve its AI. Its privacy notice also allows some ad sharing.
Strengths and weaknesses
Comet
- Free on Mac, Windows, iPhone and Android
- Can act on pages, not just sum them up
- Your sessions sync between phone and computer
- A synced account lets Perplexity record your browsing history
- The helper has to read the pages you visit
- No Linux version
Comet is Perplexity's web browser, with an AI helper beside every tab. It can sum up a page or compare products across sites. It can even work through a multi-step task while you browse. Bigger jobs go to Perplexity Computer. It's free on Mac, Windows, iPhone and Android, and your sessions sync between them. The trade-off is privacy. The helper has to read your pages, and a synced account lets Perplexity record your history.
Full Comet review
Grok
- Up-to-the-minute answers on news and trends
- Strong reasoning models on paid plans
- Image and video generation for subscribers
- Deepfake scandal led to probes in several countries
- Closely tied to X and its data practices
- Best models and Grok Imagine require a subscription
Grok stands out for real-time knowledge pulled from X, so it is quick on breaking news and trending topics. Paid plans add Grok 4.7 in Expert and Heavy modes, plus Grok Imagine for images and video. It is looser with content limits than most rivals, and that backfired in January 2026, when sexualized deepfakes made with Grok triggered investigations in the EU, UK and beyond. Privacy and safety remain the weak spots.
Full Grok review
