Augustin,
Welcome to the Forum. I am wondering if your boat electronics are wifi enabled? If they are it maybe that your iPad is attempting to log onto that and in doing so disabling location services. Does the same thing happen when you run the navigation app (or any other gps dependent service) on your iPhone?
Simon
edited by simoncurrin on 1/9/2018

Hi Agustin,
I do not have an answer to your question, but if you do not get an answer here on the Forum, you might try Attainable Adventures Cruising web site. It will cost you ~~20USD to join, but some of the discussion streams have been very active in regard to IPad use for navigation with many skippers reporting using them extensively. Any question posted will go out to all the people involved and I would suspect there would be great interest in your query: both in a warning of its occurrence and in solutions. I would also suspect you would get some good ideas pertaining to the IPad’s use in this area. Not to mention all AAC has to offer in other areas.
If you do follow up to AAC, let me know how it works out and, please, report what you do find as the IPad seems to be many people’s back-up and sometimes their primary.
My best, Dick Stevenson, s/v Alchemy

Hello: I wonder if this has happened to someone in his boat:
I have an Ipad with Navionics app installed. Everything works perfect until I switch on my electronics main switch( Tridata, GPS, Autopilot, Plotter)in my sailing boat. It is like it looses his internal gps signal(IPad) and then, it does not work anymore. If I jump to the pontoon and go further than a couple of meters, it works again. By the time I return to the boat, it freezes. It is like if my IPad were not compatible with some magnetic field created by my boat when I switch on my electronics. So, I cannot use my IPad as a standby plotter, if I do not want to loose all my electronics, including autopilot.
Thank You for the advice..Cheers, Agustin.