Loading dependency graph, done.
BUNDLE [android, dev] ....../index.js ▓▓▓▓▓▓▓▓▓▓░░░░░░ 64.3% (667/832)::ffff:127.0.0.1 - - [02/Oct/2018:04:30:46 +0000] "GET /index.delta?platform=android&dev=true&minify=false HTTP/1.1" 500 - "-" "okhttp/3.10.0"
error: bundling failed: SyntaxError: C:ReactNativemrnnode_modulesreact-nativeLibrariesComponentsSwitchSwitch.js: Support for the experimental syntax 'optionalChaining' isn't currently enabled (103:41):

101 | // Support deprecated color props.
102 | let _thumbColor = thumbColor;

103 | let _trackColorForFalse = trackColor?.false;
| ^
104 | let _trackColorForTrue = trackColor?.true;
105 |
106 | // TODO: Remove support for these props after a couple releases.

Add @babel/plugin-proposal-optional-chaining (https://git.io/vb4Sk) to the 'plugins' section of your Babel config to enable transformation.
at _class.raise (C:ReactNativemrnnode_modules@babelparserlibindex.js:3939:15)
at _class.expectPlugin (C:ReactNativemrnnode_modules@babelparserlibindex.js:5253:18)
at _class.parseSubscript (C:ReactNativemrnnode_modules@babelparserlibindex.js:5959:12)
at _class.parseSubscript (C:ReactNativemrnnode_modules@babelparserlibindex.js:2716:51)
at _class.parseSubscripts (C:ReactNativemrnnode_modules@babelparserlibindex.js:5944:19)
at _class.parseSubscripts (C:ReactNativemrnnode_modules@babelparserlibindex.js:2669:52)
at _class.parseExprSubscripts (C:ReactNativemrnnode_modules@babelparserlibindex.js:5934:17)
at _class.parseMaybeUnary (C:ReactNativemrnnode_modules@babelparserlibindex.js:5903:21)
at _class.parseExprOps (C:ReactNativemrnnode_modules@babelparserlibindex.js:5812:21)
at _class.parseMaybeConditional (C:ReactNativemrnnode_modules@babelparserlibindex.js:5784:21)
BUNDLE [android, dev] ....../index.js ▓▓▓▓▓▓▓▓▓▓▓▓░░░░ 77.5% (752/854), failed.