| feature/os version | iOS 4.3.2 | iOS 5.0 | iOS 5.1 | iOS 6.0 | android 1.6 | android 2.1 | android 2.3.3 | android 3.0 | android 4.0.2 | android 4.1.1 |
|---|---|---|---|---|---|---|---|---|---|---|
| Object.create | yes | yes | yes | yes | no | no | yes | yes | yes | yes |
| Object.defineProperty | yes | yes | yes | yes | no | no | yes | yes | yes | yes |
| Object.defineProperties | yes | yes | yes | yes | no | no | yes | yes | yes | yes |
| Object.getPrototypeOf | yes | yes | yes | yes | no | yes | yes | yes | yes | yes |
| Object.keys | yes | yes | yes | yes | no | no | yes | yes | yes | yes |
| Object.seal | no | yes | yes | yes | no | no | no | no | yes | yes |
| Object.freeze | no | yes | yes | yes | no | no | no | no | yes | yes |
| Object.preventExtensions | no | yes | yes | yes | no | no | no | no | yes | yes |
| Object.isSealed | no | yes | yes | yes | no | no | no | no | yes | yes |
| Object.isFrozen | no | yes | yes | yes | no | no | no | no | yes | yes |
| Object.isExtensible | no | yes | yes | yes | no | no | no | no | yes | yes |
| Object.getOwnPropertyDescriptor | yes | yes | yes | yes | no | no | yes | yes | yes | yes |
| Object.getOwnPropertyNames | yes | yes | yes | yes | no | no | yes | yes | yes | yes |
| Date.prototype.toISOString | yes | yes | yes | yes | no | yes | yes | yes | yes | yes |
| Date.now | yes | yes | yes | yes | yes | yes | yes | yes | yes | yes |
| Array.isArray | yes | yes | yes | yes | no | no | yes | yes | yes | yes |
| JSON | yes | yes | yes | yes | no | yes | yes | yes | yes | yes |
| Function.prototype.bind | no | no | no | yes | no | no | no | no | yes | yes |
| String.prototype.trim | yes | yes | yes | yes | no | no | yes | yes | yes | yes |
| Array.prototype.indexOf | yes | yes | yes | yes | yes | yes | yes | yes | yes | yes |
| Array.prototype.lastIndexOf | yes | yes | yes | yes | yes | yes | yes | yes | yes | yes |
| Array.prototype.every | yes | yes | yes | yes | yes | yes | yes | yes | yes | yes |
| Array.prototype.some | yes | yes | yes | yes | yes | yes | yes | yes | yes | yes |
| Array.prototype.forEach | yes | yes | yes | yes | yes | yes | yes | yes | yes | yes |
| Array.prototype.map | yes | yes | yes | yes | yes | yes | yes | yes | yes | yes |
| Array.prototype.filter | yes | yes | yes | yes | yes | yes | yes | yes | yes | yes |
| Array.prototype.reduce | yes | yes | yes | yes | no | yes | yes | yes | yes | yes |
| Array.prototype.reduceRight | yes | yes | yes | yes | no | yes | yes | yes | yes | yes |
| Getter in property initializer | yes | yes | yes | yes | yes | yes | yes | yes | yes | yes |
| Setter in property initializer | yes | yes | yes | yes | yes | yes | yes | yes | yes | yes |
| Property access on strings | yes | yes | yes | yes | yes | yes | yes | yes | yes | yes |
| Reserved words as property names | no | yes | yes | yes | no | no | no | yes | yes | yes |
| Zero-width chars in identifiers | no | no | no | yes | no | no | no | no | no | yes |
| Strict mode | no | yes | yes | yes | no | no | no | yes | no | yes |