SidePilot iOS app natively supports the BLE mini for use with Arducopter via Serial telemetry link.

Example setup for BLE mini for use with SidePilot
You can now incorporate Bluetooth 4.0 Low Energy (BLE) technology
easily in your project with our BLE Mini. BLE Mini requires only a
serial port for communication so it supports all major development
platforms that have UART interface including Arduino, Raspberry Pi,
Netduino, BeagleBone etc. In addition, we provide you with access to all
Ti's CC2540 I/O pins and the ability to upload firmware via USB, making
the BLE Mini an ideal development/prototyping board for your BLE
project/accessory/Appcessory.
Features
Simple interface - with our pre-loaded firmware code name 'Biscuit',
you could easily connect to any development board or IC with UART
interface.
Compact form factor - (L)39mm x (W)18.5mm x (H)3.8mm this is a very
popular request from makers using smaller Arduino boards like Arduino
Mini/Micro/Nano/Pro Mini etc.
Support Central or Peripheral role - it can connect to other BLE Mini or BLE Shield, not just iOS device.
Standalone operation - Texas Instruments (TI) CC2540 is a SoC
(System-on-Chip) IC that can operate without any external
microcontroller. You can develop your own firmware using IAR Embedded Workbench for 8051 Compiler , all I/O pins of CC2540 are accessible.
Hardware Overview

Hardware Overview

RedBear BLE Mini - Bluetooth 4.0 Low Energy Module
- Product Code: RBL-BLE-Mini
- Availability: 1
-
$20.00
Tags: Redbear, ble mini, redbearlab, redbear ble mini