When comparing WhatsApp vs SecureChat, the Slant community recommends SecureChat for most people. In the question“What is the best team chat software?” SecureChat is ranked 22nd while WhatsApp is ranked 54th. The most important reason people chose SecureChat is:
Supports threads to organise conversations into topics.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Straightforward interface
The interface is very simple, fast and easy to use. You can start using it as soon as the app has been downloaded - it does not require setting anything up or registering. You can communicate with anyone in your contacts list that also uses WhatsApp. Includes useful features like seeing when a contact is currently available or typing.
Pro Widely used
WhatsApp reported 1.5 billion users in 2018. Your friends are most likely already using WhatsApp, so it's easy to get setup.
Pro Effortlessly builds your contacts by using your phone number as identification
WhatsApp will automatically find all of your contacts currently using Whatsapp and add them to your contacts. This makes it really easy to setup and given that it's the most popular messaging app it's likely that a lot of your contacts are already using it.
Pro Message mirroring on web app
WhatsApp can be used from the desktop via Chrome, Firefox and Opera browsers. Accessing it requires using the Android app to scan the QR code that's presented on web.whatsapp.com.
Pro Signal protocol
Whatsapp uses the state-of-the-art Signal protocol that ensure strong end-to-end encryption.
Pro One-on-one texts can be encrypted
WhatsApp has implemented end to end encryption for messages sent on it's service. Even WhatsApp has no way to read a users messages.
Pro Threads to organize conversations
Supports threads to organise conversations into topics.
Pro Expiring messages
Channels can be configured to have expiring messages that get automatically deleted after a pre-defined time.
Pro Guaranteed delete
Ensures messages are fully deleted and removed from backup.
Pro Servers 100% hosted in Switzerland
Protected by Swiss data privacy - some of the highest data privacy laws in the world.
Pro Encryption
Strong end-to-end encryption of messages and files.
Pro Drag and drop files
Drag and drop documents, photos, videos into the chat.
Pro Integrates with other tools
Built in integrations for Zendesk, Trello, Github, SupportBee, etc.
Cons
Con Shares meta data with Facebook
WhatsApp shares your messaging meta data with Facebook if you do not opt-out in the settings. If you use the same phone number for WhatsApp and Facebook, the profiles can easily be linked.
See https://www.whatsapp.com/faq/en/general/26000016
Con Tied to carrier phone number
WhatsApp cannot be used by people without a smart phone with an active cell plan. If your phone is lost or damaged, or if your phone number changes, you cannot get messages sent by friends without them updating your phone number. You cannot send message to them until you are able to get SMS messages at your phone number.

Con Proprietary
Not open source.
Con Hard to migrate history cross platform
Migrating your chat history from Android to iOS or the other way around is not so simple. In some cases it requires a 3rd party app and in some the only way is to migrate specific chats one by one.
Con Web interface uses message mirroring
To use your computer to send messages your phone must be on with a consistent data connection.
Con Single device
You cannot use the same WhatsApp account on multiple devices (e.g. a tablet, a PC and a cellphone). The account is tied to the device with the specific cellphone number. Chat history is deleted when you sign in to a new account, unless you have created a backup.
Con No cloud sync
Messages are not stored on WhatsApp server for privacy and security reasons.
Con Limitation on shareable file sizes
WhatsApp now allows users to share files of any type, but there is still a 16 MB size limit.

Con Non-free / Propritary Software
The code base isn't free/libre and cannot be self-hosted, therefore there is no proof that encryption or "guaranteed delete", actually work. There is no reason to think this application is secure.
