I am really at odds at time with claims on data privacy and I am sure unintentionally many iPhone owner do a disservice to their fellows
Whilst I agree Apple privacy policies are quite admirable many seem to fail to note that it only applies to mostly native apps and services on their servers and then not all.
With non native apps (3rd party) you are likely to be in the same boat of self awareness of that software supplier be you an IOS or Android user, of course both OS's give some measure of control and permissions etc but that's your choice and nothing to do with Apples privacy umbrella.
There are thankfully many good app developers but there are also bad ones that have been mining data for years as Apple only recommend developers only request for essential data for the app functionality
Even Apple have similar control to the ones noted above if you post or share data:
"Apple does not claim ownership of the materials and/or Content you submit or make available on the Service. However, by submitting or posting such Content on areas of the Service that are accessible by the public or other users with whom you consent to share such Content, you grant Apple a worldwide, royalty-free, non-exclusive license to use, distribute, reproduce, modify, adapt, publish, translate, publicly perform and publicly display such Content on the Service solely for the purpose for which such Content was submitted or made available, without any compensation or obligation to you"
Or when it comes to find my phone even Apple tells you to read the T&C's of 3rd parties:
"Apple and its partners and licensors may provide certain features or services (e.g., Find My iPhone, Find My Friends) that rely upon device-based location information using GPS (where available) and crowd-sourced Wi-Fi hotspot and cell tower locations. To provide such features or services, where available, Apple and its partners and licensors must collect, use, transmit, process and maintain your location data, including but not limited to the geographic location of your device and information related to your iCloud account (“Account”) and any devices registered thereunder, including but not limited to your Apple ID, device ID and name, and device type.
You may withdraw consent to Apple and its partners’ and licensors’ collection, use, transmission, processing and maintenance of location and Account data at any time by not using the location-based features and turning off the Find My iPhone, Find My Friends, or Location Services settings (as applicable) on your device. When using third party services that use or provide location data as part of the Service, you are subject to and should review such third party’s terms and privacy policy on use of location data by such third party services"
Whilst I'm sure most good apps are relatively safe lets not get confused with what is only applicable to Apple and what else you may use on your iPhone