Petal vs Wren
| Petal | Wren | |
|---|---|---|
| Free plan | Yes | No |
| Free trial | No | No |
| Paid from | $2.55/mo | — |
| Open source | No | No |
| Platforms | extension, Web | macOS |
| Free plan | Yes | Yes |
| Paid from | 4.99 /user/mo | — |
| PDF annotation | Yes | Yes |
| Browser capture | — | Yes |
Both are listed in Best Reference Management Software, Best Citation Management Software. On Samsung Mobile US Press, Petal scores higher on our published basis.