Takes over a minute to jump from field to field on Android

I have a form with 16 pages, each with 2 or more fields, and most have simple validation rule or calculation; and it is in Chinese.  It loads OK, but it takes over  a minute to go from one field to the next after I complete my input.  I have tried this on an old Nexus 7 tablet and a Samsung Note 4.  I was able to move through the fields in the same form on an old iPad 2 with no issues.  It "appears" the system is looping through every field on the form before it moves to the next.

Am I missing something or is that the current level of support on Android? 

I use javascript for most fields because of the limited support on Mobile platform.  For example, because I cannot use the defaultValue or the required properties, I end up setting the default value to a single blank, leave the format as None and use the following validation logic to ensure an integer is entered for a required field ..

//VALIDATION for integer field

event.rc = true;

if (!(isNaN(event.value)) && event.value !== " ") {

  if (((event.value<0) || (event.value>99))) {

  app.alert("无效值：必须大于或等于 0 并小于或等于 99 的整数。");

  event.rc = false;

  } else if ((Math.round(event.value)) != (event.value)) {

  event.value = Math.round(event.value);

  }

} else if (event.value !== " ") {

  app.alert("无效值：必须大于或等于 0 并小于或等于 99 的整数。");

  event.rc = false;

}