On January 31, 2021, all numbers in Ivory Coast go from 8 to 10 digits.
it will therefore be necessary to add the appropriate prefix according to the telephone number.
In other words, for 100 contacts, this maneuver will have to be carried out 100 times, again it will be necessary to know the prefix to add.
The 10 digit app does it for you with just one click.
NB: the application is free and works without an internet connection. therefore does not recover your telephone contacts under any circumstances.