Add contacts to a group and hide this group
1-Create a group from Contacts (the Contacts application opens, choose the Groups tab, open the menu and select Create option).
2-A name is assigned to the group (please do not use a group name as obvious as I used) and added to the contacts there who want to hide from the agenda. Save the group.
3-Return to the initial screen of the Contacts application (where the list of all contacts appears) press the menu button and choose "Contacts to Display".
4-On the next screen choose "Custom List" (should be at the bottom).
5-Finally, on the next screen all about leaving all boxes marked on the right, except the respective checkbox group was first created.
What we are doing here is showing on the agenda all contacts available except those found in the created group. These will not be visible on the agenda.
Save contacts on the SIM and then "hide SIM"
This second form is basically the same as the first, except that in this case the contacts you want to hide stored in SIM memory. All other contacts should be stored in phone memory (to save a contact there is an option to choose where to save it). In the Contacts application menu "Contacts to display"> "Custom List" is selected and there all available boxes are marked, except that it belongs to the "SIM".
The two methods described here have been done in a Samsung Galaxy S3. The procedure should be similar on other phones Samsung Galaxy. In other brands the procedure may vary, but in general, should be basically the same. The key is that the application of "Contacts" installed in your phone has those options here.
Obviously, since supondrás what to do to bring back those hidden contacts visible: the end only opened the box to activate the hidden group or the "SIM" to appear again in the list of contacts or agenda.
If this "trick" is not enough, the ultimate solution so that only you and nobody else has access to your contact list is using an application that blocks access to it with a code. Droid Protector, an application of which we have discussed here can be a good option.