ChatChart is a free Android app developed by DevKey Apps that provides statistical analysis of WhatsApp conversations. This app does not require any device permissions, internet access, or collection of device data. To obtain the statistics, simply export the individual or group chat from WhatsApp to ChatChart.

Once the chat is exported and analyzed, ChatChart displays the statistical data with bar graphs. The analysis includes statistics on messages per user, words per user, letters per user, emojis per user, deleted messages of each user, media files shared by each user, links per user, messages per day of the week, messages per hour, messages per month, and messages in the last few days.

Additionally, ChatChart provides information on the top emojis and words used in the chat, as well as the top shared links. It also shows the most messaged days and the first and last messaged date and time of each user.

ChatChart does not require special permissions to work and operates in isolation without accessing the internet or device data. It also offers a useful function called "Fast Message" which allows you to create/open a new WhatsApp chat from the recipient's phone number without adding it to the contact list in advance.

Overall, ChatChart is a convenient and user-friendly app for analyzing WhatsApp conversations and gaining insights into chat statistics.