Am thinking of getting the new Echo and the larger echo with a screen. I have grandkids coming for the summer I want to know if they can still use the Alexa and echo if I am out and have my phone with me . Can they control it by using a tablet .
Echos do not need the presence of your mobile smart-phone with the Alexa app.
In fact, most people with Echos don't ever use the Alexa app after the initial setup.
Echos with screens can be set-up from their own screens and never need the intervention of the Alexa app on a smart-phone.
Echos can also be managed from Alexa app on a tablet or from the Alexa website https://alexa.amazon.co.uk/