ChatGPT is the better app overall, scoring 9.0 to 8.1. ChatGPT wins on 4 of the 5 scores, Dia on 1.
People who want one AI assistant for writing, research, images and everyday questions
Office workers who juggle email, docs and meetings in the browser
Score by score
The details
| Feature | ChatGPT | Dia |
|---|---|---|
| Category | AI Assistants | AI Assistants |
| Category rank | #1 of 16 | #12 of 16 |
| Developer | OpenAI | The Browser Company |
| Pricing | Free + paid plans | Free + paid plans |
| Usable for free | Yes | Yes |
| iPhone & iPad | ✓ | — |
| Android | ✓ | — |
| Mac | ✓ | ✓ |
| Windows | ✓ | ✓ |
| Web | ✓ | — |
Common questions
Is ChatGPT better than Dia?
ChatGPT is the better app overall, scoring 9.0 to 8.1. ChatGPT wins on 4 of the 5 scores, Dia on 1.
Which is cheaper, ChatGPT or Dia?
ChatGPT: Free plan with ads in some countries; Plus $20/month; Pro from $100/month. Dia: Free browser has no AI; Better Answers is $10 a month and Better Days $100. On value for money, ChatGPT scores higher.
Do ChatGPT and Dia work on the same devices?
Only ChatGPT runs on iPhone & iPad, Android, Web.
Which is more private, ChatGPT or Dia?
Dia scores higher on privacy (8.2/10). History, chats and files are encrypted on your device, and Sync is end-to-end encrypted. AI partners can't train on your data. Dia keeps some unlinked content 30 days to improve itself unless you opt out.
Strengths and weaknesses
ChatGPT
- Widest feature set of any AI assistant
- Polished apps on phone, desktop and web
- Free plan runs on the latest model family
- Free and Go plans show ads in some countries
- Chats train models by default unless you turn it off
- Top models and higher limits require a paid plan
ChatGPT is the most complete AI assistant you can get. It writes, codes, searches the web, talks back in voice mode, makes images and can work through long tasks with its ChatGPT Work agent. GPT-6 now powers every plan, and memory and projects keep context across chats. The catch: the Free and Go plans show ads in several countries, and your chats train models unless you opt out.
Full ChatGPT review
Dia
- Calm, uncluttered design from the makers of Arc
- Data is stored and encrypted on your device
- AI partners are barred from training on your data
- New users' free plan has no AI features
- Better Days plan costs $100 a month
- Windows version is still an early build
Dia comes from the team behind Arc and puts an AI chat beside your tabs that can read what's open and pull in context from Slack, Notion and Teams. Its Morning Brief, meeting prep and deck building are aimed squarely at office work. Privacy is better than most AI browsers, with your data stored on your device. Since August 2026, though, new users get no AI on the free plan, and the Windows version is still young.
Full Dia review
