1) Any plans to connect other brokers for stocks? Or, can I at least track my portfolio for B3 (Brazilian Stock Exchange)
Alpaca coming next. After that there are a bunch we can integrate with but no promises on when.
As for portfolio tracking - this is on our radar (integration with Plaid). If it does happen this year, it would be at the tail end of the year.

2) Regarding Crypto, since the system do all the trading, how safe is my data?
Short answer: very. We encrypt your keys and only decrypt when trades are occuring. The trade module is also in a private VPC - ie. hard to access.

3) If someone hacks your system, can they use the connection to transfer my crypto? Or, this is technically impossible? Please clarify
This is not possible. Brokers allow you to limit the permissions of a given set of API keys. Aikido won't ask you to permission your API keys to transfer coins out of your account. We've done everything we can to ensure the security of the app.

4) Can I use my own algo? I'm developing an algo using python to use with Binance, which language yours use?
We're working on custom strategies right now! so the answer is soon :) Though this will all be no-code. You won't be able to plug your code into Aikido this year at least.