I change my passwords about every 6 months on my phone. I am a bit OCD about it. They have found a backdoor through the Samsung. I had to set up bunches of wifi and security apps and programs to keep them out.
My friend is a Apple fan but her iPhone had been hacked before. No smartphone is perfect and 100% secure.
No, my husband will not go for iPhone. He is looking into one of those military type phones. Way expensive than iPhone. He has been researching lately but he hasn't decided yet. Just learned Boeing makes Boeing Black phone for security firms. It is pretty cool it comes with self-destruct feature.
