Wemos with ESP32 - LoLin32
Popular Wemos D1 with WiFi chip ESP8266 has other member of Wemos family, now with ESP32.

On aliexpress is available a new development board with ESP32 $6.90 + shipping by Wemos. LoLin32.

LoLin32, development board including ESP32, microUSB, reset button and LED. The board has integrated battery charger for Li-Ion.

Microcontroller: ESP-32
Operating Voltage: 3.3V
Digital I/O Pins: 26
Analog Input Pins: 12
Clock Speed(Max): 240Mhz
Flash: 4M bytes
Length: 5.8mm
Width: 2.54mm
Weight: 5.8g

LoLin32 wiki website https://wiki.wemos.cc/products:lolin32:lolin32

Link to LoLin32 https://www.aliexpress.com/store/product/WEMOS-LOLIN32-V1-0-0-wifi-bluetooth-board-based-ESP-32-4MB-FLASH/1331105_32808551116.html

Originaly shared http://www.cnx-software.com/2017/04/21/6-90-wemos-lolin32-esp32-development-board-comes-with-4mb-flash-lithium-battery-support/