How well does the ReSound LiNX2 9 RIE 62 work with an Android smartphone? Are there any limitations compared to an iPhone?

Dan Schwartz's answer was very thorough. The shorter answer: any cell phone will work with the ReSound LiNX or LiNX2 wireless hearing aids if you have a ReSound phone clip. You can use them for phone calls with Samsung Galaxy or Note phones with Bluetooth 4.0, but you won't hear anything else through the hearing aids without a phone clip. You can hear it all with an iPhone or iPad or iPod Touch with Bluetooth 4.0 without needing a phone clip.

About the only problem I've run into with the LiNX2 hearing aids and phones is when the phone operating system updates, the hearing aids need to be re-paired to the phone. It's not a flaw in the hearing aids, but a known issue with the phone software that it forgets its knows Bluetooth connections and you have to set it up again. Since it only takes a minute, it's usually a minor issue.

ReSound LiNX, Enzo, LiNX², and Enzo², and Beltone First, Legend, Boost, & Boost+ hearing aids work well with compatible Android phones. However, with Android there is no A2DP stereo streaming. From the ReSound Smart Hearing Aid Compatibility page:

ReSound Smart is compatible with the following Android devices**:

Please note: Direct stereo streaming, which is available via the iOS platform, is not currently available through Android platforms at this time. Android users can stream stereo audio using the ReSound Unite Phone Clip+ which allows you to connect your ReSound hearing aids to any Bluetooth-enabled mobile phone.

• Samsung Galaxy S7
• Samsung Galaxy S7 Edge
• Samsung Galaxy S6
• Samsung Galaxy S6 Edge
• Samsung Galaxy S5
• Samsung Galaxy S4
• Samsung Galaxy Note 4
• Samsung Galaxy Note 5
• All subvariants of the phones listed above (ex. Samsung Galaxy S5 Active, Samsung Galaxy S6 Edge+, etc.)

**All phones must be running either Android KitKat (4.4.2 - 4.4.4), Lollipop (5.0 or higher) or Marshmallow (6.0.1). You can also find details on Android device compatibility in the description for the ReSound Smart app at Google Play or under 'About the ReSound Smart app' in the app's Settings. Please note: hearing aids may need to be updated to the latest firmware to work with the app.

Also, I need to add, you cannot upgrade the firmware on ReSound, Beltone, or Danalogic i-Fit (UK NHS) hearing aids via AirLink wireless programmer: A wired connection from a HiPro, NOAHlink, or proprietary SpeedLink along with correct programming adapter is required.