你登陆之后把数据保存在本机数据库不就行了，再次登陆，判断有没有账号信息

在手机端保存账号对应的 token， 参考 iOS登录及token的业务逻辑

 可以保存在 sharedpreferences中

你这是需要做一个app实现这个功能？还是只要一个东西用来存账号密码？安卓端的用sharedPreferences,懂一点安卓的话调用这个类几行代码就可以实现了

干货！

https://www.cnblogs.com/tinyphp/p/3998444.html

package com.kuaihuoct.TestTool.utils;

import android.content.Context;
import android.content.SharedPreferences;
import android.content.SharedPreferences.Editor;

import java.util.Map;

/**
* SharedPreferences工具类，用于写入和读取键值对
*/
public class SharedPreferencesUtil {

public static final String shareFile = "ELeadCommon";

public static final String user_id= "user_id";
public static final String bt="position";


public static final String shareFileInMulitProcess = "ELeadCommon_MulitProcess";

public static boolean getBoolean(Context context, String key) {
SharedPreferences settings = context.getSharedPreferences(shareFile,
Context.MODE_PRIVATE);
return settings.getBoolean(key, false);
}

public static boolean getBoolean(Context context, String key, boolean defaultBoolean) {
SharedPreferences settings = context.getSharedPreferences(shareFile,
Context.MODE_PRIVATE);
return settings.getBoolean(key, defaultBoolean);
}


public static boolean putBoolean(Context context, String key, boolean value) {
SharedPreferences settings = context.getSharedPreferences(shareFile,
Context.MODE_PRIVATE);
Editor edit = settings.edit();
edit.putBoolean(key, value);
return edit.commit();
}

/**
* 读取String类型值
*
* @param context
* @param key
* @return
*/
public static String getString(Context context, String key) {
SharedPreferences settings = context.getSharedPreferences(shareFile,
Context.MODE_PRIVATE);
return settings.getString(key, "");
}

public static boolean putString(Context context, String key, String value) {
if (context == null)
return false;
SharedPreferences settings = context.getSharedPreferences(shareFile,
Context.MODE_PRIVATE);
Editor edit = settings.edit();
edit.putString(key, value);
boolean commit = edit.commit();
return commit;
}


/**
* SharedPreferences 记录集一次性保存，提高存储效率
*
* @param context
* @param valueMap
* @return
*/
public static boolean putValueMap(Context context, Map<String, Object> valueMap) {
if (context == null)
return false;
SharedPreferences settings = context.getSharedPreferences(shareFile,
Context.MODE_PRIVATE);
Editor editor = settings.edit();

for (String key : valueMap.keySet()) {
Object value = valueMap.get(key);
if (value instanceof Boolean) {
editor.putBoolean(key, (Boolean) value);
} else if (value instanceof String) {
editor.putString(key, (String) value);
} else if (value instanceof Integer) {
editor.putInt(key, (Integer) value);
} else if (value instanceof Long) {
editor.putLong(key, (Long) value);
}
}

boolean commit = editor.commit();
//清空Map集合，避免重复存储数据信息
valueMap.clear();
return commit;

}

/**
* 读取String类型值, 不同进程同步的模式
*
* @param context
* @param key
* @return
*/
public static String getMulitString(Context context, String key) {
SharedPreferences settings = context.getSharedPreferences(
shareFileInMulitProcess, Context.MODE_MULTI_PROCESS);
return settings.getString(key, "");
}

public static boolean putMulitString(Context context, String key,
String value) {
SharedPreferences settings = context.getSharedPreferences(
shareFileInMulitProcess, Context.MODE_MULTI_PROCESS);
Editor edit = settings.edit();
edit.putString(key, value);
boolean commit = edit.commit();
return commit;
}

/**
* 读取Long类型值
*/
public static long getLong(Context context, String key) {
SharedPreferences settings = context.getSharedPreferences(shareFile,
Context.MODE_PRIVATE);
return settings.getLong(key, -1);
}

public static boolean putLong(Context context, String key, long value) {
SharedPreferences settings = context.getSharedPreferences(shareFile,
Context.MODE_PRIVATE);
Editor edit = settings.edit();
edit.putLong(key, value);
return edit.commit();
}

/**
* 读取Int类型值
*/
public static int getInt(Context context, String key) {
SharedPreferences settings = context.getSharedPreferences(shareFile,
Context.MODE_PRIVATE);
return settings.getInt(key, -1);
}

public static int getInt(Context context, String key, int defaultValue) {
SharedPreferences settings = context.getSharedPreferences(shareFile,
Context.MODE_PRIVATE);
return settings.getInt(key, defaultValue);
}

public static boolean putInt(Context context, String key, int value) {
SharedPreferences settings = context.getSharedPreferences(shareFile,
Context.MODE_PRIVATE);
Editor edit = settings.edit();
edit.putInt(key, value);
return edit.commit();
}

}

用 SharedPreferences 就可以实现,我的就是这样实现的,希望可以帮助你.

你这到底是个手机上浏览的网站，还是一个需要在手机上安装的APP。

先把这事整明白，再让大伙帮你想办法。