You likely mean the DS Lite (released 2006), not "DSL." Here's a detailed breakdown of the differences.
| Feature | DS Lite | DSi |
|---|---|---|
| Release | 2006 | 2009 |
| Screens | 3.12", 256x192, 4 brightness levels | 3.25", 256x192, 5 brightness levels (brighter) |
| Cameras | None | 2x 0.3 MP (VGA) – Front & Rear |
| Storage | GBA Slot (Slot-2) only | SD Card Slot (up to 32GB) + 256MB Internal |
| Software | DS Cartridges only | DS Cartridges + DSiWare (Digital Shop) + Browser + Photo/Music Apps |
| Audio | Stereo Speakers | Improved Speakers + Audio Recording/Playback |
| GBA Backward Compat. | Yes (Slot-2) | No (Slot-2 Removed) |
| Battery Life | 15–19 hrs (Lowest brightness) | 9–14 hrs (Lower due to CPU/RAM boost) |
Both play the full Nintendo DS library. The 3DS family plays both DS and DSiWare titles natively.