Unfortunately Android doesn't have default integrated functionality to notify user periodically about missing calls/messages/other notifications via sound (only LED is blinking). This opensource tool allows to monitor notifications from any applications which are important for You and perform sound reminder periodically
Copyright 2015 Eugene Popovich
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
<http://www.apache.org/licenses/LICENSE-2.0>
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
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