I have a small custom 5V 2mA device which is powered over USB. To be specific, it will be powered over USB by connecting it to an Android smartphone or an iPhone. There is no data transfer. I currently use an OTG Type A connector (i.e., shorting the ID and GND pins on the phone), but a non-OTG connector (i.e., floating the ID pin) also successfully delivers power from my particular phone.
Are there any phones out there which would give me power for an OTG connection, but give no power for a non-OTG connection? My understanding of the USB specification is that this is allowed (and maybe even preferred to preserve the phone battery), but I'm simply hoping it does not happen.
The above question was intended for phones with micro-USB Type A ports (since I'm really not sure what a Type C OTG cable would be). So, to also cover the latest technology, are there any current phones with Type C ports where the resistance on the CC1/CC2 pins changes my power?