README updates (#41)

* README updates

* typo

README.md

@@ -72,11 +72,14 @@ interface Signer extends SignerInterface {
 }
 ```
 
-The app can use all or any of these, depending on needs. To instantiate the `@polkadot/api` with the provider (app does not have it's own) and the signer (allowing the extension to sign messages) can be done via -
+The app can use all or any of these, depending on needs. To instantiate the `@polkadot/api` signer (allowing the extension to sign messages) can be done via (assuming a known, single extension) -
 
 ```js
 import { ApiPromise } from '@polkadot/api';
 
-const { signer } = window.injectedWeb3;
-const api = await Api.create({ signer });
+const pjsx = await window.injectedWeb3['polkadot-js'].enable('my dapp');
+const accounts = await pjsx.accounts.get();
+const api = await Api.create({ signer: pjsx.signer });
 ```
+
+Generally, you would probably want to have access to all extensions available and have a slighly higher-level interface to work with. For these cases, [extension-dapp](packages/extension-dapp/) provides a cleaner interface around the injected object, making it simpler to work with from a dapp perspective.

packages/extension-dapp/README.md

@@ -3,7 +3,7 @@
 A basic extractor that manipulates the `window.injectedWeb3` to retrieve all the providers added to the page. It has a number of utilities -
 
 - `web3Enable(dappName: string)` - to be called before anything else, retrieves the list of all injected extensions/providers
-- `web3Accounts()` - returns alist of all the injected accounts, accross all extensions (source in meta)
+- `web3Accounts()` - returns a list of all the injected accounts, accross all extensions (source in meta)
 - `web3FromAddress(address: string)` - Retrieves a provider for a specific address
 - `web3FromSource(name: string)` - Retriebes a provider identified by the name
 - `isWeb3Injected` - boolean to indicate if `injectedWeb3` was found on the page
@@ -19,10 +19,12 @@ import { web3Accounts, web3Enable, web3FromAddress } from '@polkadot/extension-d
 const allInjected = await web3Enable('my cool dapp');
 
 // returns an array of { address, meta: { name, source } }
+// meta.source contains the name of the extension that provides this account
 const allAccounts = await web3Accounts();
 
 // finds an injector for an address
 const injector = await web3FromAddress('5DTestUPts3kjeXSTMyerHihn1uwMfLj8vU8sqF7qYrFabHE');
+
 // sets the signer for the address on the @polkadot/api
 api.setSigner(injector.signer);
 ```