Yes, StartMail is accessible through a web browser. We specifically made it to work as if it is an app on your phone, and you can access all StartMail privacy features like encryption and aliases from here. For easy email access from a mobile phone or tablet, we recommend adding our website to the home screen of your device.
Alternatively, you can use a third-party email client such as K-9 Mail, Outlook, or Apple Mail to access your StartMail email on your phone. You will need to configure the email client to use the correct settings for StartMail. You can find instructions on how to configure your email client on our support page.