To monitor your child's activities you are supposed to install SecureTeen Child App (the one with Green icon) on child's device. While the SecureTeen Parental Control (with Blue icon) is to only check logged activities (from registered child's device) as well as alert given feature settings at dashboard i.e. without browsing SecureTeen website to access your online account. You can have this parent app on any parental phone with android OR iOS platform only.
There is no need to complete software installation on parental device too. What you will have to do exactly is; just download SecureTeen Parental Control on personal/parental device and add a device/child-profile (to map kid's phone) within parent-app. To create new child-profile you will find a Plus "+" signed tab/button on dashboard of Parental app. Once done, now please complete software installation on child's phone i.e. by following given instructions(look for 'View Instructions' tab under your newly added device/profile) inside of downloaded Parent-app.
When software will be successfully installed on your child's device, you may check its logged activities (as well as alert given feature settings) by signing into the Parent app on yours device.
NOTE: You can access you SecureTeen dashboard from anywhere, at anytime i.e. either by using SecureTeen Parent App OR by going to SecureTeen website on its LOGIN page i.e. at following URL: https://cp.secureteen.com/login.php