Form Submission problems for Android Mobile users

We are using Apricot.  We created a survey, published it and created a hyperlink to it for our clients to complete it on their phone or other device.  It works fine on iPhones.  But on Android phones, and some ipads, when users get to the end of the survey, the ‘Submit’ button is either partially or completely hidden below the users visible screen, so they cannot submit it.  Any advice?  is this a known problem?  Thank you