Lexo terms of use
This page applies to Lexo (com.lexo.keyboard), published by K4Y Apps. It is not a first-run acceptance gate - it is a published notice of the terms that govern using the app, and downloading or using Lexo constitutes acceptance of them. This is a plain-English summary, not a substitute for legal advice, and it has not been through formal legal review.
1. Acceptance
By downloading, installing, or using Lexo, you agree to these terms. If you do not agree, do not use the app.
2. Licence
Lexo itself is proprietary and closed source. K4Y Apps does not publish Lexo's source code, and these terms grant you no right to copy, modify, redistribute, or reverse-engineer the app beyond what your local law and the Google Play terms already allow.
Lexo is built as a fork of FlorisBoard, which is licensed under the Apache License 2.0. That upstream code remains under Apache-2.0, and the Apache-2.0 licence text ships with the app as that licence requires. Apache-2.0 permits a closed-source derivative, so building on FlorisBoard does not make Lexo open source. The on-device models carry their own separate licences, listed below.
3. On-device models
Lexo runs several machine-learning models entirely on your device for typing prediction and voice dictation. Each is covered by its own licence, listed below. None of these models, their weights, or your usage of them are sent off-device except as described in the privacy policy.
| Model | Licence | Used for |
|---|---|---|
| SmolLM2-360M (fine-tuned) | Apache-2.0 | Typing prediction - English |
| Qwen2.5-0.5B-Instruct | Apache-2.0 | Typing prediction - Spanish, Portuguese, French |
| Gemma 3 1B IT | Gemma Terms of Use | Typing prediction - Swedish, German, Polish (and Turkish on older Lexo versions) |
| Turkish GPT-2 (ytu-ce-cosmos, fine-tuned) | MIT | Typing prediction - Turkish |
| NVIDIA Parakeet TDT 0.6B v3 | CC-BY-4.0 | Voice dictation - English, Spanish, Portuguese, German, French, Polish |
| KBLab KB-Whisper Small | Apache-2.0 | Voice dictation - Swedish |
| Whisper Large v3 Turbo Turkish (selimc) | MIT | Voice dictation - Turkish |
4. Gemma terms pass-through
Lexo's Swedish, German, and Polish typing prediction is powered by Google's Gemma 3 1B IT model, and older Lexo versions also used Gemma for Turkish typing prediction (current versions ship a Turkish GPT-2 fine-tune instead; the Gemma terms continue to apply to installs still running the Gemma pack). Gemma is provided under and subject to the Gemma Terms of Use found at ai.google.dev/gemma/terms.
As a binding provision of these terms of use: your use of the Gemma-powered features in Lexo is subject to the Gemma use restrictions in Section 3.2 of the Gemma Terms of Use, which incorporate by reference the Gemma Prohibited Use Policy. You must not use Lexo's Gemma-powered features for any restricted use set out in that policy, or in violation of applicable law. If you further distribute Lexo, or any derivative of it that includes the Gemma model, this same obligation - that use of the Gemma-powered features is subject to the Gemma use restrictions and the Prohibited Use Policy - passes on to anyone you distribute to.
5. Disclaimer of warranty; limitation of liability
Lexo is provided "as is," without warranty of any kind, express or implied, including but not limited to warranties of merchantability, fitness for a particular purpose, and non-infringement. To the maximum extent permitted by law, K4Y Apps is not liable for any indirect, incidental, special, or consequential damages arising from your use of the app, including any output produced by the on-device models.
6. Changes to these terms
If we make material changes to these terms, we will update the "last updated" date above. Continued use of the app after any change constitutes acceptance of the updated terms.
7. Contact
Questions or concerns: [email protected].