Is there internet at Sipapu?
There most certainly is. Thanks to a simple 4G antenna on the roof, we can connect to the nearby Claro mast and get speeds of up to 13Mbps, depending on weather. Sunny, clear days seem to be best, while rainy or humid days are slower.
On average, the download speed is somewhere between 8 and 10 Mbps, upload somewhere between 1 and 2. The screenshot below is from a broadband speed test at speedtest.net on 5 May 2021.

How about cellular coverage?
Well, by the same token, you should be able to pick up decent 4G directly through hte phone. Truth is it depends on your exact location and what kind of phone you have.
The best we have seen was a Samsung Note, followed by Motorola an Huawei phones. These are able to connect well enough to send and receive messages via WhatsApp, Signal and Telegram.
With other phones, including iPhones, you have to head into the jungle in search of higher ground.
We have found various locations on higher ground within 5 mins walk from the houses where the signal is good enough for messages, voice and even video calls.
NB It seems to be the case that pay monthly contracts get better coverage than pre paid users.