Heroku app not loading on iPhone - Node / React - ios

Question

I've built a Node/React/Webpack app and just deployed it. Everything works just like on localhost for my desktop (Ubuntu 16.04 with Chrome and Firefox) and from an Android Galaxy Core phone using Chrome, but on an iPhone 5S using Safari and Firefox I don't get anything except the name of the app showing up in the title of the tab.
I don't think it's a case of CSS messing with me - I tried to go directly to one of the internal pages and it didn't redirect me to the main page like it should have, so I think it isn't loading at all.
Are there any common gotchas with this? This is the second Node/React/Webpack app I've built, using pretty similar methods, and the first one did fine on everything.
Here is my package.json file - if there's anything else that would be helpful to see just ask.
{
"name": "last-minute",
"version": "1.0.0",
"description": "connect to others nearby for last-minute hanging out",
"main": "webpack.prod.js",
"engines": {
"node": "9.5.0",
"npm": "6.1.0"
},
"scripts": {
"test": "jest --config jest.config.json",
"start": "node server/server.js",
"build": "webpack --config webpack.prod.js",
"dev": "webpack --config webpack.dev.js --mode development && node server/server.js",
"light": "webpack --config webpack.light.js --mode development && node light-server/style-server.js"
},
"author": "Doug Sauve",
"license": "ISC",
"dependencies": {
"#babel/core": "^7.0.0-beta.44",
"#babel/preset-env": "^7.0.0-beta.44",
"#babel/preset-react": "^7.0.0-beta.44",
"#google/maps": "^0.4.6",
"babel-loader": "^8.0.0-beta.2",
"babel-plugin-transform-class-properties": "^6.24.1",
"babel-plugin-transform-object-rest-spread": "^6.26.0",
"babel-polyfill": "^6.26.0",
"babel-preset-env": "^1.7.0",
"bcryptjs": "^2.4.3",
"css-loader": "^0.28.11",
"enzyme": "^3.3.0",
"enzyme-adapter-react-16": "^1.1.1",
"express": "^4.16.2",
"google-maps-react": "^2.0.2",
"jest": "^22.4.4",
"moment": "^2.22.1",
"mongoose": "^5.0.14",
"node-sass": "^4.9.1",
"nodemailer": "^4.6.5",
"normalize.css": "^8.0.0",
"raf": "^3.4.0",
"react": "^16.3.1",
"react-dom": "^16.3.1",
"react-geocode": "0.0.9",
"react-redux": "^5.0.7",
"react-test-renderer": "^16.0.0",
"redux": "^4.0.0",
"sass-loader": "^6.0.7",
"socket.io": "^2.1.0",
"style-loader": "^0.20.3",
"validator": "^10.2.0",
"webpack": "^4.4.1",
"webpack-cli": "^2.0.13",
"webpack-merge": "^4.1.2"
}
}
webpack.common.js
const path = require('path');
const webpack = require('webpack');
module.exports = {
entry: ['babel-polyfill', path.join(__dirname, `/src/main.js`)],
output: {
path: path.join(__dirname, `/public`),
filename: `bundle.js`
},
module: {
rules: [
{
test: /\.js$/,
exclude: [
path.join(__dirname, '/node_modules'),
],
use: {
loader: 'babel-loader',
options: {
presets: ['#babel/preset-env', '#babel/preset-react'],
plugins: [
['transform-class-properties', { 'spec': true }],
['transform-object-rest-spread']
]
}
}
}, {
test: /\.s?css$/,
use: [
{ loader: 'style-loader' },
{ loader: 'css-loader' },
{ loader: 'sass-loader' }
]
}
]
}
};
webpack.prod.js
const merge = require ('webpack-merge');
const webpack = require ('webpack');
const common = require ('./webpack.common.js');
module.exports = merge(common, {
mode: 'production',
plugins: [
new webpack.DefinePlugin({
'process.env.NODE_ENV': JSON.stringify('production')
})
]
});
It seems to be an issue on older versions of iOS, not sure what the breakpoint is.