The "Open in WhatsApp" app is a tool that allows users to open a chat in WhatsApp with any number without saving it first into contacts. The app was created to make this process easier and has since added multiple functionalities, such as entering a message, sharing a link, listing country codes, creating a shortcut, saving recent and pinned chats, and opening recent calls via add-on. The developer has three principles for the app: making it as small as possible, using as few permissions as possible, and not including harmful content. The app is a small tool to help users open numbers in WhatsApp without compromising their privacy.

The app is being used by some users for business purposes, and the developer requests that if the app is being used for commercial purposes, users consider supporting it. The developer wants to keep the app free of ads and purchases, and the progress and updates of the app are based on the reception and support from users. There is a donation version available for those who want to support the development. The app only uses the SHORTCUT permission to create shortcuts in the launcher, and its size is around 100KB (0.1MB).

The developer thanks those who have contributed to the translation of the app. The app is not affiliated with nor endorsed by WhatsApp Inc. The previous name of the app was "Open in WhatsApp (click to chat)", but it was changed to comply with WhatsApp guidelines. The app is a helpful tool for users who want to open a chat in WhatsApp without saving the number first, and it is designed to be small, secure, and free of harmful content. Users who find the app useful can support the development by donating to the developer.

Overall, the "Open in WhatsApp" app is a useful tool for users who want to open a chat in WhatsApp without saving the number first. The app is designed to be small, secure, and free of harmful content, and the developer requests that users consider supporting the app if it is being used for commercial purposes. The app only uses the SHORTCUT permission to create shortcuts in the launcher, and its size is around 100KB (0.1MB). The developer thanks those who have contributed to the translation of the app and emphasizes that the app is not affiliated with nor endorsed by WhatsApp Inc.